NGC 6001. See NGC 6002. ===== NGC 6002 may be a star 1.9 arcmin south of NGC 6001. It was found by Lord Rosse while he was examining NGC 6001 = H III 371. While he gives a micrometric offset from the galaxy (PA = 197.3 deg, distance = 97.6 arcsec), there is nothing in his place. A pretty low surface brightness spindle galaxy, MCG +05-37-026, is about an arcmin northwest of Lord Rosse's position, but it is faint enough that I doubt that he would have seen it. The star is closer to the measured position, but it, too, is quite faint. So, this remains a bit of a mystery. The galaxy that Wolfgang chose as N6002 is much too faint to have been seen visually, even with the 72-inch. I would put my money on the star and some kind of measuring error. ===== NGC 6014 = IC 4586, which see. ===== NGC 6018 may also be IC 1150, which see. ===== NGC 6020 = IC 1148, which see. ===== NGC 6027 is the brightest galaxy in Seyfert's Sextet. There is some confusion about the designations for the six objects in the modern catalogues, but they are fairly easy to sort out. Nevertheless, I have retained the original letter designations assigned by Carl Seyfert in his 1951 PASP paper, in spite of my "rule" mandating positional notation in multiplets. I also find it curious that Stephan saw only one of the galaxies here. As well as NGC 6027 itself, Seyfert's "a" and "b" are probably bright enough to be seen visually, especially in the 70-cm reflector that Stephan was using. Note also that Hickson and a few others considers "e" to be simply a tidal extension of N6027. This it may be, but I've retained the separate listing. ===== NGC 6028 = NGC 6046, which see. ===== NGC 6039 = NGC 6042. The description in Swift's list 4 reads "sp of 3," though it should be "sf of 3." Swift's positions in the Hercules Cluster area are not very good, and a few of his objects -- including this one -- are not identified with certainty. In defense of his positions, Swift claims that they agree well enough with Stephan's for the objects in common. This is true. It is also true that Swift's other positions for Hercules Cluster objects are much further off the mark. Did he perhaps fudge the numbers a bit for the three objects common to both lists? The others are NGC 6040 and NGC 6041, both pairs of galaxies. Also see NGC 5736 for another of Swift's nebulae which have different positions in different of his lists. ===== NGC 6040. See NGC 5736, as well as NGC 6039 = NGC 6042 where I suggest that Swift might have fudged his position for this to make it agree better with Stephan's micrometrically-measured place. ===== NGC 6041. See NGC 6039 = NGC 6042. ===== NGC 6042 = NGC 6039, which see. ===== NGC 6044 = IC 1172, which see. ===== NGC 6046 = NGC 6028. WH's RA is 3 minutes 20 seconds of time too large. Re-reducing his observation reduces the error to 3 minutes of time. Since the NGC position is copied correctly from the GC, the 20-second error is probably a reduction error of some sort. The larger 3-minute error could be a clock- reading or transcription error. Fortunately, Dreyer gives WH's complete description in a note in the Scientific Papers: "A neb suspected by 157 and the suspicion strengthened by 240, but the latter power does not remove all doubt. It follows 3 pB stars making an arch [concave towards np or nnp direction by a diagram]{Dreyer's comment}, south of which arch there is a still brighter star." Dreyer probably gave the whole description since Bigourdan twice searched unsuccessfully for WH's nebula. The arch is there, but is concave toward the northeast. The "still brighter star" to the south is SAO 101676. The configuration is so striking that there is no doubt about the identification. ===== NGC 6049 = SAO 121361. JH's description reads, "A * 7m which I am strongly incline [sic] to think has a nebulous atmosphere about 2 arcmin in diameter." There is no trace of nebulosity on modern photographs, and the star has a normal A2 spectrum. It is a spectroscopic binary, but that would not have been a factor in JH's observation. ===== NGC 6050 = IC 1179, which see. ===== NGC 6052 = NGC 6064, which see. ===== NGC 6053 = NGC 6057, which see. ===== NGC 6054 = IC 1183. Swift notes that the neighboring star is south preceding, not south following. This points at IC 1183 as the galaxy that received the number 6054 in the NGC. In support of this, IC 1183 is considerably brighter and has a higher surface brightness than the spiral that is usually taken as NGC 6054. Bigourdan did not see the spiral, either, so the identity is virtually certain. ===== NGC 6055. See NGC 6057. ===== NGC 6056 = IC 1176, which see. ===== NGC 6057 = NGC 6053. Swift found the brightest of the two objects near this place (the other is NGC 6055) on 6 June 1886. Two nights later, he found both objects, but apparently thought both were new discoveries. It is also possible that he saw CGCG 108-127 and made a 10 arcmin error in his declination. However, this would place his position somewhat northeast of the true place of the CGCG galaxy, whereas his positions for the other objects he discovered on 6 June are generally southwest of the true places. ===== NGC 6059 is probably lost for good. I could not find it for ESGC, and there are no galaxies at reasonable offsets from the nominal position that Swift might have seen. His complete description was copied intact into NGC, and his position was correctly precessed, so the original paper was no help in this case. The IC1 note is another curiosity about the field: there is nothing at Bigourdan's "revised" position, either. There are a few faint stars and even fainter galaxies in the area, but nothing that Bigourdan could have seen. He comments under his observation of IC 4589 (which see), that he doesn't see how it would be possible to mistake IC 4589 for N6059. He's right. Finally, there are no systematic offsets in Swift's positions for the night of 6 May 1886 that might lead us to a galaxy. Another (N4280, which see) of those objects, though, is also probably lost. ===== NGC 6061. See IC 1190. ===== NGC 6064 = NGC 6052. Dreyer's note in the Scientific Papers includes the following comment: "H did not observe the nebula in the centre of the field, but applied a correction of -0.7 minutes of time, which appears to have been too small." In the 1912 Monthly Notices list of corrections, he adds, "The identity with 6052 is certain." WH's declination is the same as Marth's, whose RA is very good, too. ===== NGC 6065 and NGC 6066. When Swift finally got around to publishing these two (in his 9th list), he interchanged the declinations. Dreyer noticed this and commented on it in the notes to the first IC. Howe noticed the note, and reobserved the galaxies, showing that Swift's original positions (sent in a private communication to Dreyer) are correct. So, too, are Swift's descriptions, expanded somewhat for the 9th list. ===== NGC 6066. See NGC 6065. ===== NGC 6071 and NGC 6079 = IC 1200 are two of the brighter galaxies in a group or scattered cluster. Both were found by WH on 6 May 1791, and positions for both were referred to 13 UMi = SAO 008220. Neither place has a galaxy in it, but preceding each place by about 1 minute of time are two objects that fit Herschel's descriptions and declinations. Dreyer mentions this in his 1912 edition of WH's complete papers, and corrects the position of NGC 6079 in the IC2 notes, curiously leaving NGC 6071 unannotated. Dreyer also notes in his edition of WH's complete papers that if another star in the sweep (G.2091 = SAO 016305) is used instead of 13 UMi as the comparison, then the positions agree "well" with Bigourdan. Well .... Bigourdan's places are excellent, but Herschel's positions are still five arcmin away, and the large RA error in the NGC is traded for a large error in declination. (There is, by the way, a 10 second error in Bigourdan's listed RA for his comparison star for NGC 6071, perhaps a typo.) In any event, Herschel's relative position between the two galaxies is accurate as are his descriptions, so there is no uncertainty about the identifications once the systematic errors are removed. However, the poor NGC position for NGC 6079 led Swift to believe that it was a previously unknown nebula when he ran across it in August of 1888. He did in fact find a "new" object nearby, IC 1201, but incorrectly refers to it as the "north-following of 2" when it is actually south, as his surprisingly good position makes clear. The "south-preceding of 2" (which is actually north; again, his position is good), NGC 6079 = IC 1200 is otherwise well-described by him, including a "star 12th mag pretty close south." (His description of IC 1201 is similarly unambiguous: "double star near points to it." All three stars are in GSC.) Finally, Dreyer suggests that IC 1200 might be the same object as Bigourdan 207. This, however, is IC 1204 (which see), a galaxy north-preceding NGC 6091 by a few arcmin. Bigourdan's positions for both of these are also spot on. ===== NGC 6075 = IC 4594, which see. ===== NGC 6079 = IC 1200, which see. Also see NGC 6071. ===== NGC 6081 = IC 1202, which see. ===== NGC 6082 may be IC 4597. If so, JH's position is 2 minutes of time too small, and 8 arcmin too far north. In SGC, I made the object identical with five faint stars. Now, 20 years later, I do not see any obvious asterism of five stars near JH's place unless it is the asterism at 16 12 13.2, -34 06 30. Wolfgang chose a triple star 4 seconds of time on east. JH's description is copied accurately into NGC (in CGH, he says "25 arcsec" rather than "S") and the declination is appropriate for the sweep. All in all, this one is a bit of a mystery. I've listed the IC identity in the Table for lack of anything better. ===== NGC 6091. See IC 1204. ===== NGC 6092 is a double star at Bigourdan's place. ===== NGC 6111 is not IC 1210. In a note in IC1, Dreyer says, "In Swift's list IX, the declination for 1890 is given as +63 32.6. It was 62 deg in the MS. communication sent me in 1887." That the more northerly declination is correct is confirmed by the note in Swift's published paper (but not carried over into the NGC) "Double star near south points to it." Unfortunately, the incorrect declination in Swift's letter to Dreyer has led to two incorrect identifications for the number. The first came from Bigourdan -- his "corrected" position quoted in the IC2 notes is for a star. The second came from the modern catalogues which equated the number with a galaxy that Swift also coincidentally discovered, IC 1210 (it was independently found by Bigourdan, presumeably while searching for N6111). In any case, the two numbers apply to two separate objects. ===== NGC 6122. Even though Bigourdan's description for this galaxy is hardly appropriate ("vF, R, no N"; the object may be very faint, but it is nearly edge-on, and has a very bright nucleus), his position -- with the minutes of declination corrected in the IC2 Notes -- falls within 3 arcsec of the object. There can be no doubt about the identity. ===== NGC 6125 = NGC 6127 = NGC 6128. There are only two galaxies in this area (the other is NGC 6130), but four NGC numbers. NGC 6125 = H II 810 is the brighter of the two, so is almost certainly the galaxy that WH saw, though he must have made an error of 20 arcmin in reading the NPD (see Dreyer's note in the Herschel Papers, 1912). Herschel's original NPD is coincidentally identical to that of NGC 6130; this has led Reinmuth to suggest that NGC 6125 = NGC 6130. But the RA's are 51 seconds different, and Dreyer does not mention any problem with the RA's in Herschel's sweep. Dreyer's conclusion that the minutes of NPD recorded by Herschel (59) should be 39 is the most reasonable explanation. Swift has two objects near the correct place for the brighter galaxy, both from his 4th list, but found about a week apart on 28 June and 6 July in 1886. The descriptions of these two are similar ("pF, vS, R" and "pF, pS, R, BM"), and also agree with Herschel's description ("pF, pS, lE"). Therefore, I am almost certain that the three observations all refer to the same galaxy. A third object found by Swift, also on 28 June 1886, is preceded by a bright star (SAO 29889) that he noted in his description; this verifies the identification as NGC 6130. The star is not mentioned by Herschel, further evidence that he saw the brighter northern galaxy and not this one. ===== NGC 6127 = NGC 6128 = NGC 6125, which see. ===== NGC 6128 = NGC 6127 = NGC 6125, which see. ===== NGC 6130 is the fainter of a pair of galaxies. See NGC 6125 = NGC 6127 = NGC 6128 which is the brighter. ===== NGC 6132 = IC 4602, which see. ===== NGC 6133 may be the triple star listed in the table; this is near Swift's place, and it may be close enough together to have been mistaken for a nebula by him. It may also be CGCG 276-012, but this is mere guesswork. Swift has not left us much to go on -- the NGC description is copied correctly from his original list. Of the three other galaxies found the same night by Swift, NGC 6262 (which see) is also missing. NGC 6206 and NGC 6279 are close to their nominal positions, with no significant systematic offset. ===== NGC 6135 may be CGCG 320-015. The bright central part of the galaxy fits Swift's description, and there are two stars near it. However, the position is 4.4 minutes of time and 5 arcmin off, so I am not convinced that this is the correct object. The double star that Wolfgang chose is probably too faint to be Swift's object. Since I don't see anything else in the area that might be Swift's nebula, I've put the CGCG object in the Table with a question mark. ===== NGC 6138 = NGC 6363. I had earlier thought that N6138 might be one of the galaxies in the northwestern part of Abell 2199 near NGC 6145 and NGC 6146. Stephan has clearly misidentified his comparison star: he calls it "Arg. Z. +41 deg 2821" which I take to be BD +41 deg 2821. But that is one hour on east from the position Stephan gives for his comparison star, and there is no star near his position. However, in his introduction to his re-reduction of all of Stephan's observations, published in 1916, Esmiol mentions that NGC 6138 is the same nebula as NGC 6263. Because the other case that he mentions in the same sentence (NGC 983 = NGC 1002) is clearly true, I had thought that we could also accept this one as given. However, Steve Gottlieb and Albert Highe followed up on this and found that Stephan's implied offsets don't match any nearby star for NGC 6263 while they do for NGC 6363. So, Esmiol's note, N6138 = N6263, is a misprint and should read N6138 = N6363. I'm grateful to Steve and Albert for pointing this out. I also thank Jim Caplan at Marseilles Observatory for sending Esmiol's introduction and several pages of his tables; these have helped with various of Stephan's observations. ===== NGC 6141 is a faint galaxy at Bigourdan's measured offset. The NGC position, correctly copied from the Comptes Rendus article, is 3 arcmin to the south. It may result from an inaccurate estimated position for the comparison star. This might also be IC 4606 (which see), but its position is well off that of the object that Finlay saw. ===== NGC 6144 may also be IC 4606, which see for the story. ===== NGC 6145. See NGC 6138 and NGC 6147. ===== NGC 6146. See NGC 6138 and NGC 6147. ===== NGC 6147 is the middle (and faintest) of a line of three galaxies including N6145 and N6146 (the brightest). LdR's diagram shows all three, as well as another fainter galaxy that he mistook as a star. ===== NGC 6151 is an asterism of 8-10 faint stars at JH's position. It is positively identified by his comment that it "... is pointed to by 2 small stars 9m and 14m; the *9m is the only one of that magnitude within 6 arcmin." ESO mistakenly chose a very faint galaxy well east of JH's position, which is not only very good, but was copied correctly into the NGC. ===== NGC 6164 and NGC 6165 are the two brightest lobes of the bipolar nebula associated with HD 148937, a hot, young, active star. These nebulae used to be called "planetaries", but we now know them to be the result of energetic winds from young, massive stars, rather than the dying gasps of dwarf stars like the Sun. These two fairly bright patches of ionized gas neatly flank the HD star. Deep exposures show more, though fainter, nebulosity closer to the star. JH picked these up in South Africa, and noted the star as a double. If it is, it is a close double, not resolved on the short-exposure V plate scanned for the DSS. ===== NGC 6165. See NGC 6164. ===== NGC 6166 has been a thorn in the side for cataloguers since Holmberg included it in his multiple galaxy list in 1937. There is no problem with the identification of N6166 itself. It is the brightest in Abell 2199, but is also composed of several interacting galaxies. And that is part of the problem. Briefly, Holmberg's companions are not part of the galaxy itself, but are separate galaxies in the cluster surrounding N6166; all are 2-3 arcmin away, and all have magnitudes around B = 15.5 to 16. None of them are in RC3. On the other hand, Minkowski found in the late 50's that N6166 is itself made up of several components (see his classic paper on the system in AJ 66, 558, 1961). The three brightest are easily visible on the POSS1 prints, while the fourth is almost lost in the overexposed blur of the second. These are all within 5 or 10 arcsec of the "center" of N6166. The first three had separate entries in RC1, and the fourth is mentioned in the notes (the RC1 notes are wrong when they say that these are the Holmberg companions), but since they are clearly parts of the main galaxy itself, we dropped them from RC2 and RC3. Their positions are (measured by me with respect to 2 nearby GSC objects, one a galaxy, the other a star): Component RA (1950) Dec A 16 26 55.3 +39 39 37 B 16 26 56.2 +39 39 42 C 16 26 56.0 +39 39 35 D 16 26 56.4 +39 39 39 For the entire N6166 complex, GSC has: A - D 16 26 55.57 +39 39 37.9 which is just about what a magnitude weighted mean of my individual measures would give. Unfortunately, RNGC followed RC1, but (of course!) managed to confuse the identifications and did not give the Holmberg letters for the individual objects. I've also found in my copy of MCG the identifications that we had adopted before we sorted out the mess then. I've put them in square brackets because they were never published -- by us, at least! -- and shouldn't be. But if one were going to assign suffixes based on the Holmberg list, and wanted to make these suffixes similar to the others in use (starting with capital A rather than little b), then these are the suffixes that would be assigned. I think that this is what RNGC was trying to do. Anyhow, here are the correct identifications for the five Holmberg galaxies: Ho 751 BO MCG +7-34- RNGC CGCG [RC2 1st cut] a 1 60 6166 224-039 [N6166] b 24 50 6166D --- [N6166A] c 53 76 6166B 224-045 [N6166B] d 15 48 6166C --- [N6166C] e 12 56 6166A --- [N6166D] The "BO" numbers are from a paper by Harvey Butcher and Gus Oemler in which they give positions, magnitudes, and colors for nearly 200 galaxies in the cluster (ApJS 57, 665, 1985). In addition, there are two Zwicky compact galaxies nearby: I Zw 153 No. 1 = BO 61, and I Zw 153 No. 2 = BO 95. ===== NGC 6168 is probably CGCG 109-028 with a 1m 30s error in Swift's RA (the Dec is close). He has a faint star at the preceding end of the galaxy, but the star is actually at the following end. Because of these two problems, I'm not completely convinced that this identity is the correct one, but there are no other galaxies in the area that come as close to matching Swift's description. ===== NGC 6170 = NGC 6176. Swift's RA for NGC 6170 is 40 seconds of time off, but his description of the star field is accurate: "... in vacancy; many pB sts south." The declination is accurate, too, so there is little doubt about the identity, first suggested in RNGC. ===== NGC 6172 = IC 1213. Stephan's position is 10 minutes of time too large due to a misprint in his paper in AN 2661. The position for his comparison star is correctly given, however, and identifies it as SAO 141069. Once the correction is made, it's clear that N6172 is IC 1213. RC3 is correct for a change. ===== NGC 6173. See NGC 6174. ===== NGC 6174 is one of three nebulae found by Lord Rosse in 1849 while he was observing NGC 6173 (h 1962 = H III 640), and is the only one of the three included in the GC and NGC. JH took the observation from LdR's 1861 paper which lists only the three nebulae in the area found by JH, plus a terse comment "Another nearby." LdR's 1880 monograph has a fuller description of the observations, as well as a sketch of three of the nebulae. While the sketch is not labeled, it is clear from the descriptions that the one shown in the upper left is NGC 6173. A double nebula is directly north at a distance, estimated in the sketch, of 6 arcmin; while the third is an estimated 8 arcmin "east" of the second. The direction is in quotes since the diagram does not fit the sky unless LdR (or Dreyer, who prepared the monograph) got the direction wrong. Normally, the arrows in the diagrams point to the east; in this case, it must be west. LdR has another observation and sketch in 1851 which confirms the three sketched in 1849. The fourth nebula is "About 15 arcmin following and 3 arcmin north of this [N6173] there is a new neb, vF, gbM." There are no galaxies in that location that LdR might have seen -- but there is one 15 arcmin preceding and 3 arcmin north that fits his description. This is another indication that the east/west directions in this observation have been reversed. Dreyer added a note to the NGC: "Second of 3, forming a rectangular triangle, the 2 others being assumed to be h1962 [N6173] and h1963 [N6175], but the identity of the group is doubtful." Dreyer's note is incorrect in making two of the nebulae identical to JH's; only one is. The other two are "novae." LdR's final observation from 1860 suggests that he saw N6175 ("... an E neb, with a * close to f end, and either a knot or a * in p end"), but then concludes, "Found no other nebulae near. Twilight troublesome." Perhaps the last two words explain the lack of additional nebulae, though N6175 is in the midst of a cloud of rather faint galaxies in the outskirts of Abell 2199. So, we have a problem: three new nebulae found by LdR, but only one NGC number for them. Several sources have taken the double nebula north of N6173 as N6174. I am reluctant to do this as Dreyer called N6174 only "vF" making no mention of the duplicity. Of the two nebulae north and west of N6173, I favor calling the brightest of these (which is also the closest to N6173) N6174. LdR observed and sketched this twice, whereas he has only one observation of the other. ===== NGC 6175. See NGC 6174. ===== NGC 6176 = NGC 6170, which see. ===== NGC 6187. There is a faint possibility that this is also NGC 6191. See that for more. ===== NGC 6189. This may be NGC 6191, too. See that for more. ===== NGC 6190. Is this possibly NGC 6191, too? See that for more. ===== NGC 6191 is not to be found at its nominal place. There are several other bright galaxies in the area, however, that Swift might have picked up. Possibilities include NGC 6187, N6189, or N6190. N6187 has the two stars preceding that Swift noted in his description, but it is the faintest and smallest galaxy of the candidates. In addition, it has a bright star (SAO 29975) 3.5 arcmin north that Swift surely would have noted. N6189 fits Swift's description best -- though the two stars are following rather than preceding as Swift notes them -- but is 50 arcmin north of his position. N6190 is 20 arcmin south, and forms a rather large equilateral triangle with two stars west and northwest. Another possibility is UGC 10271. That is 20 min 30 sec preceding Swift's position, matches his declination and description, and has the two stars preceding. If that is the galaxy Swift saw, he clearly made a transcription error in his RA. All in all, several candidates, but no clear winner. ===== NGC 6194 is the brightest of a group of galaxies also including NGC 6196, which see for the story. ===== NGC 6196 = IC 4615, NGC 6197 = IC 4616, and NGC 6199. N6196 is the second brightest of a small group of galaxies headed up by NGC 6194 (discovered by John Herschel). Marth's discovery positions for N6196 and N6197 are 38 seconds of time preceding and 1.3 arcmin north of the true positions. If this same offset applies to NGC 6199, then one of the two stars near the resulting position is likely the object that Marth saw. Though I pointed to the brighter of the two during preparation of RC2 as N6199, it has m = 12.0 in GSC which would almost surely make it unmistakeably a star in Laselle's 48-inch telescope. Thus, I now feel N6199 is more likely to be the fainter (m = 14.8 in GSC), though the position is further off (about 30 arcsec, compared to about 15 arcsec) from Marth's (corrected) position. Where did the IC objects come from? During his survey of the NGC nebulae, Bigourdan of course could not locate either N6196 or N6197 at their catalogued positions -- his estimated positions given under these numbers refer to stars. However, he did find five other nebulae in the area (B209, B324, B325, B425 and B426), and made micrometric observations of the three brightest of these. It is clear, even in Bigourdan's own notes, that B209 (the brightest) is NGC 6194, though he somehow got the position (from Schultz) incorrect (his position and Schultz's original position agree to within 10 arcsec). The other two measured nebulae have, as mentioned above, identical offsets from Marth's positions, so it is also clear that B325 = IC 4615 = NGC 6196, and B426 = IC 4616 = NGC 6197. Bigourdan searched in vain, however, for NGC 6199 at Marth's position. It's a bit surprising that he did not make the connection between the two brighter galaxies and his own, and thus search near the offset for N6199. Two other "nebulae" in Bigourdan's group had only estimated positions by him: B324 = IC 4614, and B425 = IC 4613. IC 4614 is a galaxy, but there is nothing near his position for IC 4613. See that number for further discussion of this group. ===== NGC 6197 = IC 4616. See NGC 6196. ===== NGC 6199 is probably a star. See NGC 6196. ===== NGC 6202 may be the same galaxy as NGC 6226. The description fits, there is a star near following, and the declinations are the same. The problem, of course, is the seven minute RA difference. This would not be the only large RA error in Swift's lists, of course, but it still prevents a positive identification. All in all, 9 July 1886 was not a good night for Lewis Swift. Of the three nebulae he found that night, we can now pretty surely identify only N6170 (which see). N6135 (which also see) and N6202 are far enough from Swift's positions that we will probably never know for sure which nebulae Swift actually saw. ===== NGC 6206 = IC 1227, which see. Also see NGC 6133 and NGC 6262. ===== NGC 6211 and NGC 6213 are the southern-most two of a line of four galaxies stretching southwest to northeast (the other two are CGCG 299-018 and -019, not in NGC). Swift found these in June of 1887 and sent them directly to Dreyer who included them in NGC from Swift's letters. Swift published the discoveries a few years later in his 9th list. His RAs are 15-20 seconds of time too small, but Dreyer included Bigourdan's corrections in the IC2 notes. Bigourdan's published RAs are within two seconds for each object, and his offsets, if re-reduced using a modern position for his reference star, would agree with modern positions. ===== NGC 6213. See NGC 6211. ===== NGC 6216 = NGC 6222. JH recorded the cluster on four different sweeps. On three of those (NGC 6216), his RA is accurate. However, the fourth sweep (NGC 6222) has the RA 1 min 20 sec following; the Dec is the same. The description for N6222 fits N6216, and there is only a Milky Way star field at N6222's position. The identification, adopted in RNGC and ESO, is pretty sure. ===== NGC 6219. Aside from an error of 27 seconds of time in the RA, Marth's position and description fit the galaxy well. He claims to have seen it on more than one night (it is marked "verified" in his table), so I'm a bit surprised that the RA is off so much. ===== NGC 6222 = NGC 6216, which see. ===== NGC 6226 may also be NGC 6202, which see. ===== NGC 6227 is described by JH as "A star 5m in a great cluster, or an immensely rich milky way patch." The star is SAO 227313, and it is superposed on a rich part of the Milky Way, just as JH saw it. There is a good scattering of stars between 5th and 10th magnitude within a degree or two following JH's star -- they stand out well on the Southern Sky Survey film. There are two major clumps of stars here: the southern one surrounds NGC 6231, while the northern clump is Collinder 316; Trumpler 24 is apparently a concentration in the northeastern part of Cr 316. IC 4628, a diffuse nebula, is on to the northeast of Tr 24. This whole region may be JH's "great cluster." The area to the west of SAO 227313 is heavily populated with stars of the 9th and 10th magnitude, but does not stand out as much as the areas to the east. Following JH, I've adopted the position of the SAO star. Brent Archinal alerted me to the information about the clusters in the area. Here is his note: I think there are two possibilities for this object. For one, I looked at a DSS image here (via Skyview) and there's nothing really obvious. However, with histogram equalization of a 30' and also a 90' field, there is a brightening of the Milky Way around the star of about 15-18' in diameter. I think it's most reasonable to assume that this is what JH saw. On the other hand, could it be that JH was refering to the _really big_ 3 degree grouping of stars here, including Cr 316, Tr 24, NGC 6231, and Zeta-1 and -2 Sco? On a particularly transparent night a few years ago (from here in Virginia), I saw this area well for the first time as it crossed the meridian. This is a very spectacular binocular grouping of objects. Offhand, I would think that if he was refering to such a large grouping he'd describe it better or say something clearer about the size, so I think this is an unlikely identification -- but perhaps still possible. One identification I would reject is that this is one of the individual clusters, such as NGC 6231, Tr 24, or Cr 316. The 5th magnitude star in question is on the edge of Cr 316, but this group doesn't stand out well at all, at least in the 90' field. Tr 24 is too far to the NE (part of Cr 316 probably), and NGC 6321 is quite obvious to the SE and doesn't fit the description at all. None of this information corresponds with the observation by Hirsch reported in the Monograph, but he may have just been looking at a scattered group of stars here, if not Cr 316 or Tr 24. The comment by Harrington is probably copied from Hirsch (a number of Harrington's descriptions are similar to Webb Society descriptions, but without credit), and the information from Burnham, SkyAtlas 2000.0, and Houston does not seem useful. Anyway, since JH doesn't describe any resolved stars here other than the 5th magnitude one, and doesn't make any remarks that would indicate the whole 3 degree wide grouping here, the Milky Way brightening seems the best candidate for this object. It would be nice to have some visual confirmation of this particular area to help confirm this, though. Observers, to your eyepieces! ===== NGC 6231. See NGC 6227. ===== NGC 6232. See NGC 6237. ===== NGC 6236. See NGC 6237. ===== NGC 6237 and NGC 6245 may be duplicate observations of NGC 6232 and NGC 6236, respectively. Or they may be stars. Or, they may simply be "not found." Whatever the case, these are two of a group of four nebulae that Lewis Swift found on the night of 28 June 1884; the other two are NGC 6232 and NGC 6236. Over a year later, on 11 August 1885, Swift found another nebula, NGC 6248, about half a degree south of his group. There were no other observations before Dreyer compiled the NGC, so he included all five. Looking at the area on the Sky Survey prints, we now see only three galaxies here that are bright enough that Swift could have seen them. These are NGC 6232, 6236, and 6248. Swift's RA's for the three are systematically too small by 20 to 25 seconds of time, but his declinations are very good. Looking at his positions for the missing two objects shows that the declination of NGC 6237 is close to that of NGC 6232, and that for NGC 6245 is similarly close to that for NGC 6236. In addition, his RA's for the two missing objects each have roughly the same offset from the RA's for the same two galaxies (32 seconds in the first case, 48 seconds in the other). So, I wonder if NGC 6237 = NGC 6232 and NGC 6245 = NGC 6236 -- in spite of the fact that Swift found all of the objects on the same night, and explicitly noted "1st of 4," "2nd of 4," etc, in the descriptions of all four objects. Keep in mind his method of finding positions: centering the object in the eyepiece, and reading the setting circles. Did he perhaps bump the telescope or setting circles inadvertantly after reading positions for the first two objects? Still, he used a very large field eyepiece, so it may be that he mistook stars near the galaxies as other nebulae. Or, he may have seen reflections of stars out of the field and mistook them as nebulae. Or, his eyes may have played tricks on him if he was tired. I favor the jarred telescope/setting circle hypothesis, but would not bet even a nickel on its being right. Whatever happened, the two objects do not exist, so I've simply entered them as "Not found" in the table. ===== NGC 6240 = IC 4625, which see. There is no problem in the NGC position, but the IC position -- from Barnard -- is a few arcmin off. The identity is clinched nevertheless by Barnard's note of a star near north-following. ===== NGC 6245, not found. See NGC 6237. ===== NGC 6247 = IC 1233, which see. ===== NGC 6248. See NGC 6237. ===== NGC 6262 is another of Swift's missing objects. He recorded this one on the night of 23 October 1886 when he found three other nebulae: N6133 (which see), N6206, and N6279. Only the last two are anywhere near Swift's places, and they show no systematic offset that might help us with N6262. His description is also unhelpful (eeeF, pS, R, eee diff). Two possibilities are in the area: CGCG 299-039 and CGCG 277-010. The first would require a 5 minute and 10 arcmin error in Swift's position, the second a 1.4 minute and 1 degree error. The first is the brighter of the two, and the digit errors make it the more likely candidate. However, he could have seen either object, but without further evidence, I'm not going to do more than note them as possibilities. ===== NGC 6263 is not NGC 6138 (which see) as I had earlier supposed. N6263 is an innocent bystander, the victim of a misprint in M. Esmiol's Introduction to his complete collection of Stephan's observations. The story is under N6138. ===== NGC 6270. Here is a case where Stephan's micrometric position falls exactly on the correct galaxy (the NGC position is about 20 arcsec too far north since the position for Stephan's comparison star is similarly off), yet LEDA nearly 20 arcmin south-southwest. There was no justification for this that I can see, and I'm mystified at their decision. Whatever happened, the identity is clear and Stephan's position is within three arcsec of the modern position from DSS. ===== NGC 6276 = IC 1239, NGC 6277 (a star), and NGC 6278. William Herschel found one galaxy here. It, as one might expect, is the brightest of the group, NGC 6278. Sixty years later, Albert Marth found two other nebulous objects near Herschel's object. Shortly thereafter, Stephan discovered two nebulous objects, and also included Herschel's object in his list, correcting Herschel's inaccurate position. However, Stephan did not mention Marth's two objects; I don't know if he was aware of Marth's list or not. Dreyer, faced with this rather confusing array of five positions, asked to see Marth's observing records. These apparently did not reach Dreyer until after the NGC had gone to press, as he added a note "in press" to the NGC that Stephan had seen only one of Marth's objects. The positions are close enough that Dreyer was able to correctly identify the object (NGC 6276) as m328. m327 is north preceding about three arcminutes, and was missed by Stephan. In the NGC note, Dreyer added that the missing object should have been inserted in the NGC immediately following NGC 6275. Dreyer indeed added it later to the first Index Catalogue as IC 1238. But when we turn to the sky, there are only two galaxies here bright enough to have been seen by the visual observers (a third, later catalogued as UGC 10650, has too low a surface brightness to have been picked up). The brightest is obviously NGC 6278, but what is the other? Fortunately, Stephan's micrometric position is pretty good, being off only by the amount that his comparison star's catalogued position is off (about half an arcminute). This correctly identifies the second galaxy as NGC 6276. If we then correct Stephan's position for NGC 6277 for the comparison star's offset, we find that this object is in fact a star. Assuming that Marth's two positions are in good relative agreement, we can pin down IC 1238 as a double star. The confusion crept into Bigourdan's observations, too. He correctly identified NGC 6278, but misidentified a star as NGC 6277, and actually published NGC 6276 as a "nova" in his second list of new nebulae. He later realized his mistake, and correctly equated the NGC object with his "nova" (which had by then received the number IC 1239) in his final published list of observations. His observation of "NGC 6277" is interesting in that there is a faint galaxy just a few arcseconds north-following the star he measured. Did he perhaps glimpse the galaxy, but then measure the brighter star? Sulentic, with three NGC numbers in hand, and with three relatively large galaxies in sight on the Sky Survey, misidentifies UGC 10650 as RNGC 6276, and assigns the number RNGC 6277 to NGC 6276. NGC 6278's correct identification survived even into the RNGC. ===== NGC 6277 is a star. See NGC 6276. ===== NGC 6278 is the brightest galaxy of a group. See NGC 6276. ===== NGC 6279. See NGC 6133, NGC 6262, and IC 4636. N6279 figures in the identification (or not!) of all of these. ===== NGC 6293. See NGC 6294. ===== NGC 6294 is a double star northeast of NGC 6293, a bright globular cluster. It is offset +5.5 seconds and +0.5 arcmin from the cluster; JH's positions for the two objects, both seen the same sweep, lead to offsets of +7 seconds and +0.1 arcmin. Howe's measurement of the stars' separation (PA = 315 deg, distance = 8 arcsec) is correct. Both stars have several faint companions -- presumably members of N6293 -- merged into their DSS images. ===== NGC 6297 = NGC 6298. Though Swift claims that N6297 is the "sp of 2" and N6298 is the "nf of 2", there is only one galaxy here. He discovered it on two different nights (8 July 1885, and three weeks later on 1 Aug 1885), and apparently misled into believing he'd found two objects by the difference in his brightness estimates ("pB" and "vF", respectively), added the directional indicators during the publication process. At least, that is my theory -- he has certainly done that in other cases. An interesting sidelight: Bigourdan failed to find N6298 on three nights, but on those same three nights, measured N6297 16 different times using two different comparison stars. This may well be a record number of observations by Bigourdan for a non-descript 14th magnitude galaxy. I'd be interested in knowing why he did so much work on this -- I can't find a clue in his published data. ===== NGC 6298 = NGC 6297, which see. ===== NGC 6301 = IC 4643, which see. ===== NGC 6330 is half a degree north of Swift's position. The galaxy there (CGCG 321-013) matches his description, and his note "... nearly between 2 stars" fits, too. Though I've not checked all the history on this object, I think that CGCG is the first to suggest the identity. Bigourdan's observation, mentioned in the IC2 notes, is for a star 36 seconds east and 1.3 arcmin north of Swift's nominal position. ===== NGC 6335. JH says of this, "The whole lower end of the zone is strongly affected with nebulous patches," and gives only an approximate position for it. Though included in Cederblad's catalogue of bright diffuse nebulae, there is no bright nebulosity in the area. Instead, the Southern Sky Survey films show a patchy field of star clouds, defined by the dust of dark nebulae. It is apparently these star clouds that JH saw in the spring of 1837, giving him the impression of patchy nebulosity all through his field. (Three years earlier, he happened on the same field, giving a position then about 5 minutes east; this has become NGC 6360, which see.) I've adopted the approximate center of the brightest patch of stars nearest JH's position as the position for NGC 6335. This is about a minute west of his place which lands in a relatively poor field -- in other words, in the midst of a dust cloud. ===== NGC 6344 is a double star at Lohse's position. In appearance, it matches several other of the "nebulae" found by him with the 15.5-inch (e.g. NGC 5884, also a double star, which see), and is very close to his nominal position. There is a faint galaxy about an arcminute to the north that has been taken as N6344, but it is certainly too faint to have been seen by Lohse. ===== NGC 6347 = IC 1253, which see. ===== NGC 6360. As with NGC 6335, which see, there is no nebulosity making up this "object." Instead, JH saw the bright background of the Milky Way broken up into many patches of nebulous light by the dark nebulae lacing the area with dust. The position I've adopted for NGC 6360 is about a minute of time west and 7-8 arcmin north of JH's position (like N6335, in an area pretty well covered by dust). This is the brightest cloud of stars in the area, approximately 12 arcmin across. JH's comment, "The nebula is in patches of very great extent," makes it clear that this particular cloud is not the only one he saw in the area. ===== NGC 6363 is also = NGC 6138, which see. ===== NGC 6374 = NGC 6383. JH has only one observation (in Sweep 794) of N6374, and I believe that is a duplicate of an "Omitted Observation ..." (also in Sweep 794) for N6383 listed at the end of his CGH Observations. He has two other observations of N6383, both on different nights, but with accordant descriptions. In the single observation leading to the NGC number 6374, JH identifies the bright star in the middle of the cluster as "B[risbane] 6125". I suspect this is the correct identification, but will have to check. If the number is correct, then it is SAO 208977 = HD 159176. In any event, there is little doubt that the two NGC numbers refer to the same cluster. JH probably made a bookkeeping error somewhere along the line that led him to duplicate the observation in Sweep 794. ===== NGC 6375. See NGC 6564. ===== NGC 6379. See NGC 6564. ===== NGC 6383 = NGC 6374, which see. ===== NGC 6393 and NGC 6394 are a pair of objects found 7 July 1885 by Lewis Swift. Though he describes the two as equally faint, the southern of the two objects on the sky (more than 6 arcmin south of his position) is much fainter than the northern (3.5 arcmin south of the nominal position). I'm not convinced that Swift could have seen it. In fact, he did not find it again. When he went over the field on 15 June 1890, he recovered only one of the galaxies. This time, his position was virtually identical to the one that he gave for N6393, leading Dreyer to omit it from IC1. The position is also close to the true position for the brighter galaxy. This brighter galaxy has been taken by MCG and CGCG as N6393 based on the position. However, Swift's description does not match the field. Swift says, "vvF, pS, R; 2 B sts nr n; s of 2." The comment about the two bright stars north matches the fainter southern galaxy, but not the brighter northern one. For his northern object, Swift says, "vvF, pS, R; 2 sts point to it, the nearer is D; the other and the neb. are equally distant from the D *; n of 2." For the record, his 1890 observation reads, "eeF, pS, cE; B * nearly obscures it; between it and a F*, nearer the latter." This matches what is on the sky pretty well (his double star in the first observation is the "B *" in the second, and the other two stars are there also), so I have taken NGC 6394 as the northern galaxy. I have also tentatively assigned NGC 6393 to the very faint southern object since there is no other candidate object nearby. There are many other galaxies within one or two degrees, but none have the stars near that Swift describes. Whatever he saw, it clearly needs visual confirmation. ===== NGC 6394 is probably not NGC 6393, which see. ===== NGC 6406 is a double star at Bigourdan's place. He has four micrometric observations of it, so there is no doubt about the identification. He notes a nearby star of magnitude 12.2 at PA = 265 degrees, distance = 1.2 arcmin. The position angle is actually about 95 degrees. I suspect that Bigourdan's value ought to read 85 degrees. ===== NGC 6410 is one of the few double stars from Lewis Swift's list of "nebulae" that we can confidently say that he saw. Though he believed it to be an "eeF, S, R" nebula, his additional notes "nearly between two stars; GC 4320 [NGC 6411] near north-following" make it clear that he was indeed observing the double star. His position is not too bad, but is still far enough off (over two arcminutes) that -- without his additional notes on the field -- we could not otherwise identify his object. ===== NGC 6411, found by d'A, was helpful in pinning down the identification of NGC 6410 (which see). ===== NGC 6415 is nothing more than a Milky Way field. There is no nebula obviously involved in spite of JH's brief description, "A great nebulous projection of the milky way [sic]." JH gives only an approximate RA. On the IIIa-J film, I make the RA a minute later, and the Dec 3-4 arcmin south. See NGC 6421 for more. ===== NGC 6416. See NGC 6421. ===== NGC 6419, 6420, 6422, and 6423. These were found by Lewis Swift on the nights of 1 and 17 August 1883. Because he recorded only two objects each night, I suspect that he saw the same two twice. If so, N6419 = N6423, and N6420 = N6422. His descriptions are similar enough that this is a distinct possibility. However, Bigourdan measured the four brightest galaxies in the field (there are at least six others brighter than about B = 16 nearby), and assigned the NGC numbers to them in RA order. This has the advantage of dishing out one number per galaxy, and of closely matching Swift's declinations. Swift's RAs, however, are too small by varying amounts (13 to 24 seconds of time). Also, if Bigourdan's suggested identifications are correct, then Swift's note of a "* near east" of N6423 should read, "* near north." Since Dreyer published Bigourdan's corrected positions (close to the real ones) in the IC2 notes, I'm going to accept Bigourdan's suggested identities, in spite of my reservations above. ===== NGC 6420. See NGC 6419. ===== NGC 6421 is a brighter patch in the Milky Way that matches JH's description and sketch pretty well. His position is pretty good, too. Note, however, that the NGC description (taken from GC) is wrong. The correct description, from the CGH Observations, should read something like "Cl, vL, r, connected to Milky Way." I suspect that the NGC description was copied by mistake from the CGH entry for h3702 = N6416. There is also a prime symbol missing from the 3702 in the JH column in the NGC. Neither this object nor N6415 were numbered in the CGH Observations, and JH does not have a note for either in GC indicating why he entered them there. Dreyer copied the entries unchanged into NGC, also without notes. ===== NGC 6422. See NGC 6419. ===== NGC 6423. See NGC 6419. ===== NGC 6427 = NGC 6431, which see. ===== NGC 6428 is a star. Bigourdan's position is midway between it and another star of similar magnitude, but his description mentions both objects and makes clear that he was measuring the northern of the pair: "In the neighborhood, I suspect several small stars, one of which is at PA = 195 deg, d = 8-10 arcsec." ===== NGC 6430 is CGCG 112-035. The description and declination fit well, and the RA is off by 38 seconds. Reinmuth has this as a chain of four stars, but the galaxy is clearly the object that Marth saw. ===== NGC 6431 = NGC 6427. Stephan misidentified his comparison star. Though he claims to have used BD +25 3330, the star he actually used is BD +25 3327. Applying his offsets to this star lead to a position within an arcsecond of the DSS position for the galaxy. ===== NGC 6437 is a star cloud in the Milky Way centered about 0.7 minutes preceding and 4 arcmin north of JH's approximate position. There is no nebulosity associated with it; the numerous faint stars in the area must have given the impression of nebulosity at the eyepiece during sweeping. ===== NGC 6439. I've used the finding chart in Steve Hynes book "Planetary Nebulae" to identify this planetary. Some lists have mistakenly pointed at the star about an arcminute to the north-northeast. ===== NGC 6444 is definitely OCl-1023 = Ru 132 as noted in ESO and by Brian Skiff. JH gives only an approximate position for the cluster, but calls it "A vfine L, rich sc cl of sts 12..13..m." The ESO position -- 40 seconds preceding and 2.5 arcmin north of JH's -- is good. ===== NGC 6448 is lost. It is the 60th entry in Swift's second list. Dreyer copied all of Swift's data exactly and correctly into the NGC. There are no galaxies in the area that might be Swift's object, and I can't find an obvious digit error that would lead to another (though I did not check for large errors, e.g. 10 degrees, 1 hour). Swift found no other nebulae the night of 16 July 1885, so we have no possible systematic offset to work from, either. ===== NGC 6450 (Swift II-61) is also lost. Dreyer copied the position correctly into NGC, but abbreviated Swift's description of the surrounding star field. Swift's full description is "vF, vS; B * f 8 seconds; bet 2 sts." There are several galaxies in the area that Swift could have seen, but none matching the pattern described by him. Howe also could not find the object, though he actually searched for it three nights, not just two as in Dreyer's IC2 note. ===== NGC 6455 may be the random clumping of Milky Way stars around SAO 209348 (this is about 50 seconds preceding JH's approximate position). JH, however, does not mention the bright star. His full description reads, "A very extensive nebulous clustering mass of the milky way [sic]. The stars [are] of excessive smallness, and infinite in number." ESO chooses a "concentration of stars" (not obvious to me) near JH's position, and Wolfgang Steinicke takes a small asterism of faint stars at 17 49.0 -35 27. I doubt that either of these could be JH's object. This is another case where a visual observation would be useful. ===== NGC 6456, 6463, 6470, 6471, 6472, and 6477. Here is another mess from Lewis Swift's 4th and 5th lists of nebulae. NGC 6463 and NGC 6470 were found on 9 June 1886, the remainder on 25 September 1886. All of Swift's positions fall within a group of (at least) eight galaxies. It's possible that Swift could have seen most of the objects, but only after seeing the DSS image from the POSS-II plate could I assign his numbers with any confidence to the galaxies. I also have to thank Brian Skiff for asking about the field; his questions forced a re-evaluation that I otherwise would not have made. The descriptions don't help much. All the galaxies are "eeeF, eS, R" or a close variation, and all are noted "v dif[ficult]" to "eee dif". Swift does mention that the preceding of the group is "bet[ween] 2 sts" -- but since the Galactic latitude is so low, there are enough stars around for that description to apply to virtually any of the galaxies in the group. Dreyer added the note "* nr" to N6471 and N6477; this is not in Swift's original paper, so it must be from a letter from Swift to Dreyer. In any event, there is not much to go on here that will help us assign the NGC numbers to the correct objects. If we make some reasonable assumptions -- 1) Swift saw the two brightest galaxies on his first sweep through the area, 2) he did in fact see all six 3.5 months later, and 3) his relative positions for the remaining four galaxies seen only the second night are more or less accurate -- then we can make a stab at some identifications. These are not certain by any means, and they do not agree with some previous identifications. However, they do make sense of Swift's data. On the first night, he saw the two brightest objects in the core of the group, N6463 and N6470. N6456 is reasonably isolated to the west of the core, and N6471 and N6472 flank N6470 in declination. They are also the brightest galaxies in the core after N6463 and N6470. It also is reasonable to suppose that both components of UGC 10973 contributed to the visual appearance of N6471, so I've listed both in the main table. I'm least certain about N6477, but Swift's observation places it following N6470/1/2, and between N6472 and N6470 in declination. The galaxy I've chosen matches these constraints -- but its position is still well off Swift's place. For reference, here is a table of B1950.0 positions, Swift's on the first line, and accurate positions on the second, of my suggested identifications. Object RA (Swift) Dec Discovered Other names and comments (Precise) Pos source V 76 17 42 29 +67 37.7 25 Sept 1886 CGCG 321-034 N6456 17 42 39.60 +67 36 48.6 GSC IV 55 17 43 44 +67 36.5 9 June 1886 CGCG 321-037 = MCG +11-21-022 N6463 17 43 42.27 +67 37 24.2 GSC IV 56 17 44 19 +67 37.8 9 June 1886 CGCG 321-039 = MCG +11-21-025 N6470 17 44 22.98 +67 38 18.3 GSC V 78 17 44 19 +67 36.4 25 Sept 1886 UGC 10973a = CGCG 321-038w = N6471w 17 44 20.89 +67 36 44.0 GSC = MCG +11-21-023 N6471e 17 44 26.06 +67 36 36.6 GSC UGC 10973b = CGCG 321-038e = = MCG +11-21-024 V 79 17 44 19 +67 39.9 25 Sept 1886 N6472 17 44 11.31 +67 38 58.5 NPM1 = NPM1G +67.0154 V 80 17 44 54 +67 39.2 25 Sept 1886 N6477: 17 44 38.38 +67 37 44.3 HCds Other possibilities: 17 43 16.26 +67 33 43.7 GSC Star superposed. 17 43 33.48 +67 40 17.4 GSC Extremely compact w vF arms; star superposed on nucleus? 17 44 51.37 +67 33 33.3 HCds ===== NGC 6461 is CGCG 340-017 (CGCG's guess -- CGCG 340-015 -- is wrong). The identity is clinched by Swift's description, "eF, pS, R; nr terminal * of 5 forming semi-circle." His RA is 12 seconds too large, and his declination 38 arcmin too small. ===== NGC 6463. See NGC 6456. ===== NGC 6465 is an asterism of 4-5 stars. Though well south of the equator, it was actually found by JH from Slough. He describes it only as "Suspected; small; twilight," but his position is very good. The identification was made by Howe who found the four brighter stars here on the second night he searched for the object. He describes the object as "... simply two doubles of mag. 12. In each pair, the distance is 4 arcsec, and the two pairs are 15 arcsec apart." In the DSS image, one of Howe's four stars is double, and there is a fifth star 29 arcsec north that might have added to the appearance of nebulosity in JH's sweep. ===== NGC 6466 is correctly identified in CGCG as CGCG 278-030. RC1 and RC2 followed Carlson who has incorrectly equated this to NGC 6478. Swift's full description pins down the correct object: "eF, vS, R; bet 2 sts which with 2 others form a cross like cross in Cygnus. Neb placed as gamma Cygni." The top of Swift's cross is to the west, and the galaxy is placed exactly as he says it is. ===== NGC 6467 and NGC 6468 may be identical -- but maybe not. Though Marth apparently found them on the same night (he gives a discovery date of 1864.42 for both), the positions are different by only one second of time, and the descriptions (vF, vS, lE and vF, S, R) could well be for the same object. His data are correctly copied into NGC -- and that is all the published evidence we have. There is only one galaxy here, and either of Marth's positions could apply to it. There is nothing within one second of it that Marth might have seen. Since NGC 6468 is nominally closer to the galaxy, it usually bears that name in the catalogues. There are two asterisms nearby (I called the triple star 12 seconds following Marth's position NGC 6468 earlier), but neither is within a second of time of the galaxy, so I doubt now that either is Marth's second object. Until more evidence surfaces, I'm tentatively listing the two entries as identical. But I'm also listing the asterisms, too. They are still possibilities, remote though they be. ===== NGC 6468. See NGC 6467. ===== NGC 6470. See NGC 6456. ===== NGC 6471. See NGC 6456. ===== NGC 6472. See NGC 6456. ===== NGC 6473 and NGC 6474 were both found on 22 July 1886 by Lewis Swift. However, there is only one galaxy near his position, though he clearly says he found two (there is a typo in the NGC description for N6474: for "n of 3", read "n of 2"). Swift's positions are separated by only 15 arcsec in declination, and his description for N6473 (eeF, S, R, s of 2) is not very helpful, even if it is short enough to have made it into NGC unchanged. However, his full description for N6474 is more interesting: "eF, pS, R; 3 sts in a line near and 3 others in a line point to it; e diff; n of 2." The three stars in a line near the galaxy are southeast of it, and the three stars pointing to it are to the northeast. This pins down NGC 6474 pretty well. The only thing close south of the galaxy is an 18th magnitude star that Swift could not have seen. However, to the northeast, about 30 arcseconds away, there is a 16th magnitude star that he might have seen. Is this NGC 6473? If so, Swift got his directions confused. He's done that before, so this star is a possibility for N6473. Bigourdan went further south in search of N6473. Four arcmin from Swift's place, Bigourdan found a triple star which he mistook for a nebula. He called it N6473 and measured it on two nights. On a third night, he measured another star which he thought was the same "nebula", but which he found later to be not just different, but uncatalogued as well. It has ended up with the number IC 4668 (which see). In any event, Bigourdan's triple is also a possibility for Swift's nebula. It would mean a 4 arcmin error in Swift's position, not too much of a stretch. ===== NGC 6474. Bigourdan switched his comparison star with that for IC 4668, which see. Once that is sorted out, the identity of I4668 becomes clear, and Bigourdan's position for N6474 falls within a few arcsec of the galaxy's nucleus. Also see NGC 6473 for yet another story. ===== NGC 6476 is a star cloud in the Milky Way centered about two arcmin east of JH's approximate position. In the CGH Observations, JH says "Nebula. No description. It is probably only a nebulous portion of the Milky Way." As with other star clouds that JH saw in this same part of the sky, there is no nebulosity associated with N6476, but the dense background of faint stars would have appeared faintly nebulous during a sweep. ===== NGC 6477. See NGC 6456. ===== NGC 6478 is not NGC 6466 (which see). Carlson incorrectly equates the two numbers, and RC1 and RC2 followed along. ===== NGC 6480 is a star cloud in the Milky Way closely matching JH's sketch in the CGH Observations. My estimated position for the center of the projection to the east is about 10 seconds of time west of JH's, but there is no doubt of the identity. ===== NGC 6481 is a line of four stars clearly identified by Peters's micrometric observation. Though his position is a few arcseconds east of the center of the line, the identity is certain. ===== NGC 6497 = NGC 6498. Swift found his 80th and 81st nebulae on 16 Sept and 26 Sept 1884, respectively. The positions are only 1 second of time and 32 arcsec apart, and the descriptions are close enough that the only galaxy in the area can match both. In particular, Swift says of N6497, "Close s of middle * of 3 in a line, middle * the fainter;" and of N6498, "B * nr; F * v nr." The middle star in the line is the "faint star very near," and the bright star is the eastern of the three stars. So, I'm almost certain that the two observations refer to the same object, and that Swift added the comments "np of 2" and "sf of 2" as he was preparing his first list for publication. ===== NGC 6498 = NGC 6497, which see. ===== NGC 6499 is a close double star. Discovered by Marth, he marked it "verified" in his list, so he saw it as nebulous at least twice. When the object was photographed at Heidelberg and Lick, the observers there found only a double star without nebulosity. That is how it appears today on the Palomar Surveys. Another faint star and 2-3 very faint stars just to the west may have given the appearance of nebulosity at the eyepiece. ===== NGC 6505. Is this possibly NGC 6534? See that for more. ===== NGC 6506. The position in the main table applies to a cluster just southwest of JH's place. However, he notes that it is extremely large, "filling many fields." So, his object may be the larger star cloud in which the smaller cluster sits. ===== NGC 6514. See NGC 6533. ===== NGC 6522. See NGC 6551. ===== NGC 6523 is the star-forming core of M8 at the heart of the bright northwestern part of the nebula. NGC 6526 (which see) is the southeastern part of the nebula, and NGC 6530 is the bright star cluster 10-12 arcmin following N6523. NGC 6533 (which see) applies to the entire M8 complex, and IC 1271 and IC 4678 (both of which see) apply to condensations in its eastern reaches. ===== NGC 6525. Though listed as "nonexistent" in RNGC, there is an obvious poor cluster of bright stars just where JH placed it. It covers about 10 arcmin, and has a tight core of half a dozen stars. The position I've given in the table is for this core. ===== NGC 6526 = H V 9 is probably the part of M8 southeast of the dark lane. The nebula sweeps on up to the northeast to encompass NGC 6530, the bright, well-known cluster in M8. WH found this the 22nd of May 1784, and measured the position with respect to 51 Ophiuchi. When re-reduced using the modern position for that star, WH's position for N6526 falls at 18 01 14, -24 27.6, well within the M8 complex. As Dreyer notes in the Herschel papers, the GC and NGC positions are one degree too far north due to an error by Caroline Herschel in her reduction of the position. WH describes V 9 only as "Large, extended, broad, milky figure." Thus, this could apply to any part of (or even all of) M8 (look at WH's second description of M20 = IV 41 for another almost discrepant description of the same object). Since this was apparently his first sweep across the area, and since we know his positions were rather error-prone at the time, I think that the object he saw was, in fact, M8. Giving him the benefit of the doubt, however, I think it fair to assign the NGC number, as I said above, to the southeastern section of the complex. See NGC 6533 for more. ===== NGC 6529 was apparently first seen by James Dunlop who claimed two observations of it. His description reads, "A pretty large faint nebula, round figure, 5' or 6' diameter, resolvable into very minute stars, with nebula remaining." Unlike most of Dunlop's nebulae, JH claims to have seen this one, though only once. He lists an estimated position that is close to Dunlop's and calls it "A large milky way patch, much compressed, one portion much more so." However, checking the position on the SERC IIIa-J film shows nothing more than a rather unremarkable part of the Milky Way. Nothing stands out that strikes me as something that would catch an observer's eye. Compare this to other Milky Way fields that have NGC numbers (e.g. NGC 6476 and NGC 6480) from JH's sweeps -- there is nothing obvious here. I've put the nominal position in the table. I also checked the other nebulae seen in the same sweep; all are at about the same declination, so there is no large error in that part of JH's observation. A large RA error is possible, but I found nothing in the obvious places (plus or minus one minute, ten minutes, etc.). Perhaps a visual observer can turn up something here. ===== NGC 6530 is part of M8. See NGC 6523, NGC 6526, and NGC 6533 for more. ===== NGC 6533 = M8 = H V 13. WH's position for this, reduced from the offsets published in the Scientific Papers is in a pretty empty patch of sky roughly 30 arcmin south of M8. He does give a pretty good description in his 1786 first catalogue, however. He observed it only one night, 12 July 1784: "Extensive milky nebulosity divided into 2 parts; the most northern above [larger than] 15 arcmin, the most southern followed by stars." What struck me about this was its uncanny similarity to his description of M8 given in his 1785 paper (which I unfortunately do not have a copy of), quoted by Kenneth Glyn Jones in his fine book on the Messier objects: "An extensive milky Nebulosity divided into two parts; the north being the strongest. Its extent exceeds 15 arcmin; the southern part is followed by a parcel of stars which I suppose to be the 8th of the Connaissance des Temps [i.e. M8]." WH's 1786 description reads like a simple condensation of his 1785 description. Is it therefore possible that H V 13 = N6533 is M8? WH's position doesn't encourage that interpretation. Both JH (in GC) and Dreyer (in WH's Scientific Papers which he edited in 1912) have notes about WH's problems determining the position -- as I've noted, that position is over 30 arcmin south-southeast of M8 in a barren patch of sky. But if WH was indeed looking at M8, is there any way that his offsets (4m 54s following, 38':: south of 5 Sagittarii) can be made to fit? Well, once I tracked down 5 Sgr (it is SAO 186074, not labeled as "5 Sgr" in Sky Catalogue 2000.0), it was clear that the NGC position was properly reduced (once the earlier bugs found by JH had been cleaned up. He says in GC that the offset as originally published in PT for 1786 -- 39' north -- is wrong.). Did WH observe any other nebulae that night? In particular, did he use that same comparison star? The answers are "Yes" to both questions. H V 10, H V 11, and H V 12, all = NGC 6514 = M20 = the well-known "Trifid Nebula" have a single position referred to that same star on that same night. When we reduce that position, we find that it is about 30 arcmin south-southeast of M20 in a barren patch of sky .... Yet there is no doubt that these three nebulae constitute M20 (along with IV 41); both JH and Dreyer accept that in GC and NGC. So what's going on? The short of it: WH may have misidentified his comparison star (but see also N6698, found the same night, referred to a different star). He probably used 4 Sgr = SAO 186061, rather than 5 Sgr as is printed. Once that correction is made, it's clear that NGC 6533 is, in fact, M8. WH's resultant position is about a minute of time following the brightest part of the nebula (N6523), but is more in line with the center of the entire complex as we see it on photographs. However, as Steve and I have noted before, WH's positions from these early runs of 1783 and 1784 have generally larger errors than his later positions -- he was still perfecting his observing techniques. The mystery here is this: if JH and Dreyer knew that H V 10-12 referred to the Trifid, why then did they not make the connection -- through the comparison star in common -- to the Lagoon as well? I don't see an answer to this in any of the papers I have in my collection. However, if there is any information in WH's 1785 paper that might shed some light on this, we should look at it again. M8 also encompasses several other NGC and IC objects: NGC 6523, NGC 6526, NGC 6530, IC 1271, and IC 4678, all of which see for more discussion. ===== NGC 6534 is probably lost, like so many other of Swift's nebulae. The galaxy that CGCG chooses (CGCG 322-022) is about 1.2 minutes of time preceding Swift's position, and 2.3 arcmin south. Furthermore, the surrounding star field does not match Swift's note "... in center of a semi-circle of 4 stars." In particular, there is a fairly bright star within an arcmin of the galaxy to the north. If Swift saw this galaxy, he would surely have noted the star. Are there any other candidates in the area? Galaxies that could be force fit to Swift's description include NGC 6505 (= UGC 11026), NGC 6536 (= UGC 11077), and CGCG 322-032. None of these, however, are at positions that would be even digits off of the nominal position. I don't think they are likely to be the correct nebula, either. I'm listing the CGCG identity with a question mark. It's clear to me that it is the wrong object, but there is nothing else that comes as close. ===== NGC 6536 may just possibly also be NGC 6534, which see. ===== NGC 6543 is the famous planetary near the north ecliptic pole. See IC 4677 for a bit more about it. ===== NGC 6548 and NGC 6550 = NGC 6549. There are two galaxies in this field; the brighter, NGC 6548, was found by WH in June of 1786, and given the number III 555 in his catalogue of nebulae and clusters. WH's position reduces to 18 03 55, +18 33.5 (B1950.0), about 2.2 arcmin southeast of the modern position for the brighter object. The position in GC and NGC was either reduced with respect to a rather crude position for the comparison star (101 Her), or a (simple digit?) error of -20 seconds of time has crept into the RA. The fainter galaxy was first seen by Marth in July 1864, and was rediscovered 18 years later by Stephan. Both noted the brighter object. Marth simply says "... near III 555" in his description, while Stephan says "Distinct from [GC] 4377 and [GC] 5892." Dreyer condensed that for the NGC by adding "... near m361" to Stephan's description. Since there are only the two nebulae here, and because Stephan did not measure the brighter objects he claims to have seen, we can only speculate on what his third object must have been. Perhaps it is the line of three stars east of Marth's galaxy. In any event, it is clear that Stephan and Marth found the same galaxy. Stephan's accurately measured position precesses to 18 03 38.4, +18 31 48, while Marth's less accurately estimated position precesses to 18 03 36, +18 32.2, still quite close to the galaxy. There matters would have stood had Lewis Swift not published a cryptic note in his 11th list of nebulae (AN 147, 210, 1898): "NGC 6550 = H III 555. 6550 must be struck out." The wording of Swift's original note in his "Catalogue No. II ..." (which appeared in PASP 9, 186, 1897, and in MNRAS 57, 629, 1897) makes better sense: "NGC 6550 must be struck out, as it is identical with H. III 555." Dreyer made what sense he could of all this, and has a Note in the second IC which reads "6548 = 6550, Swift in Cat. XI." (Dreyer also changed the NGC number to "6550" for H III 555 in his 1912 collection of WH's papers.) Swift was apparently trying to tell us that there are only two galaxies here, too, but his wording in the AN list just made the cataloguing problem worse. Enough people have read the IC Note that the modern identifications are thoroughly confused. An obvious predilection for the objects in RA order has also fed the confusion. In the end, though, it is clear that WH found the brighter, northeastern galaxy, while Marth saw both objects -- and Stephan not only saw the two real galaxies, but (apparently) an asterism as well. So, my position table reflects this by keeping Dreyer's original NGC number, 6548, on H III 555; and by equating Marth's and Stephan's "novae", N6549 and N6550. ===== NGC 6549 = NGC 6550, which see. Also see NGC 6548 for the full story. ===== NGC 6550 = NGC 6549 is not NGC 6548 as we have long supposed. Thanks to Malcolm Thomson and Steve Gottlieb for first directing my attention to this puzzling triplet of numbers, and to Christopher Watson for questioning the inconsistency in my earlier "untangling" of the problem. See NGC 6548 for the full story. ===== NGC 6551 refers to an object found by Leavenworth in July of 1885. He has left us a vivid sketch showing what looks like a globular cluster placed exactly between two moderately bright stars. The position on the sketch cover matches that published in the AJ list (18 02, -29 34 for equinox 1890), but there is nothing in the area that matches the sketch. The only other notes on the sketch besides the position and Leavenworth's initials read, "Drawn July 6 from sketch July 7 '85. Power 500+-." The dates are not mistakes -- the date "drawn" really does precede the date "sketched." One must be wrong. Andris and Wolfgang have taken N6551 to be the asterism of half a dozen stars near Leavenworth's position. But they do not match his sketch at all. The nearest globular cluster is NGC 6522, and while that might be seen as "vF, vS, R, rr" at -29 degrees from Leander McCormick, the stars flanking it do not correspond with those shown on the sketch. So, another mysterious L-M object. ===== NGC 6554. During the plate scanning for ESGC, I noted this as "20-30 stars in a 20 arcmin area." I don't believe that these stars are a real cluster, but they do stand out from the field enough that they could be picked up during a visual sweep. JH's comment "Has several double stars in it" also makes it clear that he was seeing the same concentration of stars. I put the center somewhat east-northeast of JH's position, but the identity is not in question. ===== NGC 6556. The problems with this object began with Sir John himself and his summary description published in the GC, then copied faithfully into the NGC. That description makes the object "F, vL, cE, lbM, rr." On the other hand, JH's original notes read "Cl VI. An oval patch comprised within limits of the field, barely resolvable into infinitely minute points, but which, without attention, appears as a great nebula 15' l; 12' br; hardly bM." Howe saw it the same way 65 years later: "I see nothin in the entire region except thousands of the minutest stars." Dreyer summarized this in the IC2 Notes simply as "No nebulosity (Ho)." The object is actually part of the complex region of star clouds and obscuring dust clouds near the Galactic Center. JH's position points to an otherwise unremarkable part of the Milky Way, comprised of, as both he and Howe saw, "... thousands of the minutest stars." I've adopted JH's position, and his description above is apt. ===== NGC 6564 is probably a triple star 1.5 seconds preceding and 1.5 arcmin south of Marth's position. There is no galaxy near that he might have seen, and the triple would probably match his view of it with Lassell's 48-inch. Marth found two other galaxies the same night (N6375 and N6379); the mean offset of their positions from Marth's is in the same direction and about the same size (1 second of time and 1 arcmin) as those for the triple. All in all, this amounts only to circumstantial evidence, but it is the best we can do at the moment. ===== NGC 6573 may be the Milky Way star cloud about 30 seconds following JH's position, but could also be the large scattered clump of clumps of stars right around his position. His description, from one night's observation at Slough, reads, "A cluster composed of 2 or 3 clusters of very small stars, and loose large ones. Perhaps an outlier of VIII. 31 [N6583]." He marks the RA with a plus/minus sign, so either grouping seems possible. This is a candidate for observation at the eyepiece. ===== NGC 6574 is probably also NGC 6610, which see. ===== NGC 6581 = IC 1280. The position that Stephan quotes for his comparison star is off by about 15 seconds of time, so the NGC position for the galaxy is also off by the same amount. Digging into the data a bit more suggests that there is an additional 2 second error in Stephan's RA, but his description "... between two very small stars" is exactly right. Bigourdan, of course, could not find N6581 at its catalogued position, but rediscovered it at its true position. Thinking it was a "nova," he included it in his third list of new nebulae. He saw it only on one night, and commented then that it is "Impossible to measure, because I cannot easily distinguish it from 2-3 vF neighboring stars." His position is therefore based on a single estimate from the same star that Stephan used, and points to the same galaxy. ===== NGC 6583. See NGC 6573. ===== NGC 6586. See NGC 6591. ===== NGC 6588 is probably one of the asterisms that I've listed in the position table. My guess is the line of three or four stars that I've marked with a colon. The southern most of these is the brightest, and is a merged double which might have looked nebulous on a night of less than perfect seeing. It is at JH's declination and is just 30 seconds preceding his RA. Otherwise, JH's description, "eF, S; among stars. A *6 m sp 10 arcmin distant," fits nicely. The star is SAO 254209. However, there are two other asterisms that might be JH's object. I've listed them with question marks. I also checked for a large blunder in the position, but found none. In particular, the other objects in this sweep (No. 708 on 8 June 1836), are in the same declination range, and at much the same RA as well. ===== NGC 6589 may also be IC 4690 (which see for more discussion). Swift's position for N6589 is about 36 seconds of time off, a mistake corrected by Barnard, and included in the IC2 Notes. Ironically, Barnard is also responsible for a mistake of his own which makes the identity with I4690 probable. Also see discussion under NGC 6590 and IC 1283 for more on this field. ===== NGC 6590 = NGC 6595 = IC 4700. JH found the brightest nebula in this group while observing at Slough; his position is good. Swift came across it and another nearby nebula nearly 60 years later in 1885, but misplaced both by about 45 seconds of time in RA from the correct positions. In a note in AN 3101, Barnard corrected the positions for both of Swift's objects, noting the identity of N6590 with N6595. He also announced the discovery of another larger, though fainter nebula (I1284) northeast of the brighter pair. (In still another note in AN 3111, Barnard also announced the discovery of yet another nebula here, I1283. See that for more). Curiously, Barnard mentions the AN 3111 note in AN 4239, but not the AN 3101 note. Had he done so, it might have alerted Dreyer to the identity of one of Barnard's nebulae mentioned there (see N6589 for the passage) with N6595. Had this happened, Dreyer probably would not have been included it in the second IC. ===== NGC 6591 may be the galaxy that I've flagged with a question mark in the table. That matches Marth's description ("eeF, vS, stell") and is not too far off his position (the RA is 12 seconds too large). However, it may not be the object that Marth saw. That object was found the same night as NGC 6586 which has offsets from Marth's position of -2 seconds of time and -14 arcsec in declination. At similar offsets (-3 seconds and -32 arcsec) is a faint galaxy with two foreground stars just to the southwest, the brighter star superposed on the galaxy itself. While this group of objects does not match Marth's description -- in particular, the galaxy is fainter than the one I mentioned in the previous paragraph, and the brighter superposed star is considerably brighter than the galaxy (why didn't Marth mention the star if he saw it?) -- its positional coincidence within Marth's usual observational errors is fairly compelling. Still, I'm keeping open the possibility that the brighter, isolated galaxy is Marth's object. It may even be possible that the asterism of five stars that I've also included in the table is the object that Marth saw. But that is the least likely option because its brightest star is nearly of the 10th magnitude, far too bright to match Marth's description. ===== NGC 6592. Swift's position is not very good, but he notes "nearly between 2 stars." Given that he was working with a large field, that comment pins down the galaxy. See NGC 6607 for more on the field. ===== NGC 6594. As with NGC 6592, Swift's note about nearby stars "between a faint and a more distant bright star" nails the identification. The bright star is SAO 17798. See NGC 6607 for more about other objects in this field. ===== NGC 6595 = NGC 6590 (which see) = IC 4700. ===== NGC 6597. Swift's comment "Difficult by proximity to a bright star" is correct -- the star is SAO 17798, the same one he mentions in his description for NGC 6594 (which see). Also see NGC 6607 for more details about this field. ===== NGC 6599 is probably also NGC 6600, which see. ===== NGC 6600 is probably = NGC 6599, though RNGC suggests NGC 6602. Marth could have seen either, but since N6599 is nearly a magnitude brighter and has a higher surface brightness as well, it is the more likely candidate. This makes Marth's declination 7 arcmin off, and I am going to suggest that the printed north polar distance should actually be "65 07" rather than "65 01". Marth's RA is exact. If Marth's RA is off instead, and this is NGC 6602, it would be 52 seconds too small; the Dec would then be just an arcmin off. Since Marth lists this as one of his "verified" nebulae, I'm more inclined to believe that the NPD he gives is in error. ===== NGC 6601. Swift's note "Near end of a curve of stars" is accurate and unambiguously identifies this galaxy. See NGC 6607 for the reason this particular identification is so important. ===== NGC 6602 is probably not NGC 6600, which see. ===== NGC 6603, a relatively small and faint cluster, is not M24. The Messier object is actually IC 4715, which see for more. ===== NGC 6605. There appears to be a +2 minute error in JH's RA, as a cluster matching his description "Loose straggling cluster; stars 10...12m" is at his declination, but 2 minutes of time preceding. There are about 30 stars of the correct magnitude scattered over a 15 arcmin by 15 arcmin area, while there are none brighter than 14th or 15th magnitude at the nominal place. ===== NGC 6607, 6608, and 6609. This is a trio of objects all credited to Lewis Swift. They were all discovered on the night of 4 Aug 1883, and are listed in Swift's first paper as being the 5th, 6th, and 7th of 8, respectively (numbers 91-93 in his sequential numbering of the entire list). The other five objects are N6592, N6594, N6597, N6601, and N6617. Though Swift's positions aren't too good for these five, either, the galaxies are nevertheless unambiously identified by Swift's comments about nearby stars (or the lack of them). N6601, by the way, is the only other object of the eight that Swift found that night in 1883; the remaining four are dated 14 June 1885. Swift's declination for NGC 6608 is the problem. He places it at exactly the same declination as NGC 6609 just 15 arcsec north of NGC 6607. So, while there are three galaxies in the area, only two are at Swift's declination while the other is 2 arcmin south. Furthermore, the southern object is a faint edgewise Scd or Sd with a low mean surface brightness. Not only does it not match Swift's descriptions of shape ("R", "R", and "lE" for the three objects) it is so faint (around V = 15.5 at a guess, compared to V = 14.5 and 15.0 for the other two) that I would be surprised if Swift could have seen it at all. The object that Swift described as the faintest of the batch of eight (NGC 6617, which see) is considerably brighter than than this spindle. In addition to that, Swift says there is a "vF star near" his object -- there are none near the spindle that he could have seen that are not nearer NGC 6609 (and that leads to yet another hypothesis for NGC 6608; see the last paragraph of this note). Still, there are three galaxies here, and three NGC numbers. If we assume that Swift's RA's for the four objects found this night are correct among themselves in a relative sense, then we can apply the correction necessary to make his RA for NGC 6601 agree with the GSC position (+13 seconds of time) to the others. This leads to RA's for the others that are different from the true RA's by -4, -4, and -3 seconds of time, respectively. Thus, Swift's RA's for the three galaxies are in very good relative agreement. So, in spite of my doubts that he saw the faint edgewise galaxy (MCG +10-26-024), I'm going to assume a 2 arcmin error in the declination for this object and call it NGC 6608. The other two, NGC 6607 and NGC 6609, fit his descriptions very well -- including the "F star near" NGC 6609 -- so there is no problem with them. As a final possibility, I'm going to suggest that perhaps, just perhaps, Swift's observations of the latter two objects (numbers 92 and 93 in his list) refer to the same galaxy. Had the observations been made on different nights, I would have said "A-ha!" at the beginning of this story and equated them with hardly a doubt left. As is, we'd have to assume some sort of blunder in Swift's observations within a single night in a small area of sky. With that third galaxy just south, though -- well, Occam's razor slashes deeply enough that that is the more likely choice. ===== NGC 6608. See NGC 6607. ===== NGC 6609. See NGC 6607. ===== NGC 6610 is probably NGC 6574. There is nothing at the catalogued position of N6610, and there are no reasonable changes to the calculated offsets (+1m 0.11s, -4' 31.3") from Stephan's nominal comparison star ("208 W. (A.C.) H.XVIII") that point to anything aside from very faint stars. However, about 1.3 deg north, and 1.75 minutes following Stephan's nominal position is a star-galaxy pair that matches the offsets to within Stephan's normal observing errors (the actual offsets are +59.77s and -4' 32.5"). The galaxy, UGC 11198, also matches his description pretty well. So, I had taken this to be a very good candidate for NGC 6610, with some sort of confusion in Stephan's observing records. But the question about the identity had originally come from Leos Ondra who posted it to one of the astronomy forums on the Internet in 1999. There, it attracted the attention of Steve Gottlieb who did the same kind of digging back into the literature that I did, but did not come up with a candidate. Brian Skiff suggested that NGC 6574, about 5 minutes west, might be N6610, but noted that there is no comparison star at the correct offsets. Leos also noted a paper by Seares in PASP 28, 122, 1916 titled "Identification of NGC 6610." Brian checked a copy of that paper and found that the object Seares suggests is actually a plate defect on an early plate of the area. The object is not on either POSS1 or POSS2. Finally, Leos sent me a copy of a note that he had had "off-list" from Jim Caplan, a research astronomer at the Observatoire de Marseille where Stephan observed and was director between 1866 and 1907. Jim called attention to a monograph containing a complete re-reduction of Stephan's observations by a Monsieur Esmiol, presumeably one of the younger astronomers at Marseille. This was published in 1916 after Stephan's retirement, and carries not only the reduced positions, but mean values of Stephan's micrometric measurements, too. (I had seen a copy of this at the library at ROE in the late 1970s, but failed to make a photocopy for myself -- bad move!). The observation previously leading to the NGC number 6610 is listed in the monograph under the designation "anonyme" with completely different offsets (-1m 42.63s, -0' 14.0" from six settings in RA and 3 in Dec) from a completely different star (BD +14 3453). A footnote reads "Class\'e \`a tort 6610" ("Called 6610 by mistake"); this is apparently the only published "explanation" of this particular case. Reducing these observations with the GSC position for the comparison star puts the position directly on NGC 6574. So, it looks like Brian is correct, though for a different reason than he probably envisioned. I am still curious, however, about the extraordinary coincidence of the earlier calculated offsets with the UGC 11198/BD +16 3447 pair. Where did Stephan's originally published positions come from? Jim tells me that many of Stephan's original observing records and reductions are still in existence; we may be able to eventually find an answer to this question. ===== NGC 6616. Though Swift's RA is off by 24 seconds of time, Herbert Howe found the correct galaxy and remeasured its position. His correction is included in IC2. ===== NGC 6617. Swift not only describes this as the largest, faintest, and most difficult of the eight objects he found in the area, he also says that it is "in [a] vacancy." While there are faint stars nearby, the ones he would have noticed are far enough away that the object does indeed appear to be pretty isolated. See NGC 6607 for more on this field. ===== NGC 6625. JH's RA is marked uncertain in his 1833 PT catalogue where he describes it only as "A loose straggling cluster of stars 11 .. 12 m." There is no immediately obvious cluster at his position, but about two arcmin northwest there is a clump of stars, four arcmin by two arcmin in size, that might be his object. This is on the southeastern edge of a much larger clump (roughly 10 arcmin by 8 arcmin) that could also be JH's object. Neither is particularly striking, but the former has been identified as a real cluster. Since it stands out a bit more, and might make an impression during a sweep, I've adopted it as N6625. ===== NGC 6634 is probably the asterism of four stars at La Caille's position, but some doubt remains. JH inserted the GC number into the GC's "Supplementary List" at the very end, without any notes as to why he was doing so. It's probable that he had seen the note in Auwers's 1862 reprinting of La Caille's list. Auwers called attention to the declination being a degree too far south for M69, and also commented on Piazzi's note to the same effect that also included M70 (see the GC and NGC Notes for JH's rejoinder under the entry for M69 = GC 4411 = NGC 6637). In any event, La Caille's position would be 20 arcmin off M69 without the one degree error. His description -- "It resembles a small nucleus of a comet" -- fits M69 so well that Messier and many others have adopted the identity without even commenting on the position error. Glen Cozens, however, argues that M69 is too faint (at V_total = 7.7) for La Caille to have seen with his 0.5-inch aperture telescope on the mural quadrant that he used to measure southern stars from the Cape of Good Hope, and further points out that the asterism of four stars is at La Caille's position. However, if La Caille saw M69, it is not the faintest object that he found. That is the globular cluster NGC 4833 at V_total = 8.4; La Caille also found M83 = NGC 5236 at V_total = 7.5 with a somewhat lower surface brightness than M69. So, M69 is clearly still a candidate. La Caille's description is initially puzzling, though. But we need to keep that 0.5-inch telescope in mind. While he says that he had access to larger instruments, he also apologizes to his readers for rarely using them to examine the nebulae and clusters that he discovered. Given all this, his description makes perfect sense: the asterism, even though it is 4.0 arcmin across with a total V magnitude of 6.90 (Tycho-2 system), would appear as a faint blob of light. By way of analogy, I recall my first view of NGC 7150 (which see) in my 6-inch reflector in the early 1960's: it appeared as a very small, elongated nebula. Yet on the POSS1 plates, it is a simple asterism of four stars (total V magnitude of 12.0) that is almost a direct copy of the asterism at La Caille's position, but faintened by 5 magnitudes and shrunk by a factor of about 50 in diameter. It must look in the 6-inch much as the four stars would look in a 0.5-inch telescope. Cozens reports that the asterism is an unresolved blob in 12x60 binoculars, and is easier to see than M69 in the same instrument. Given all this, I'm inclined to take La Caille's position and description at face value and keep L I-11 = NGC 6634 as a separate object. However, there is a possibility, however slender, that it could be identical to M69 = NGC 6637, so I include that as an alternative. ===== NGC 6637 may possibly also carry the number NGC 6634, which see. ===== NGC 6647, H VIII 14, was also seen by JH whose position is adopted in NGC. There is nothing obvious at that position. WH's original position is about 8 arcmin west-northwest of his son's. Just 4 arcmin northeast of that is a group, about four arcmin across, of a couple of dozen stars. The brightest is around 12th magnitude. I think that these are the stars that WH took to be a cluster. What I find curious about this object is the description. NGC follows GC exactly in calling the object a "Cl, L, Ri, lC, sts vS." How did JH get that out of his father's and his own observations? WH's description reads, "A cl of sc pL sts," while JH's reads "A very loose parcel of v small stars, hardly noticeable as a cluster." "Large" perhaps, but "Rich"? Perhaps JH penned the description in haste. Whatever the case, the clump of stars that I believe to be WH's object does not match the NGC description, though it does fit what WH himself wrote. ===== NGC 6655 was found in June 1855 by Winnecke with the 9-inch Fraunhofer refractor in Berlin and has not been seen since. Auwers lists it as the 42nd new object in the appendix to his 1862 reduction of WH's nebulae where he gives Winnecke's description. This boils down to pF, S, E, 10 x 3 arcsec. The position is 18 25 43, -06 06 for 1830. There is nothing there. (Auwers also notes that he could not find the object.) However, 20 seconds of time west, and 3.3 arcmin north is a 14th magnitude double star with a separation of about 11 arcsec. This may be the object that Winnecke saw. ===== NGC 6659 appears to be a clump of about 20 stars between 10 and 15 mag covering an area about 9 x 5 arcmin. JH describes it tersely, "A v poor cluster 8th class." His position is about 2 arcmin southwest of the center of the clump of stars. ===== NGC 6660 = NGC 6661. Swift's declination for N6660 is 10 arcmin too small, but his description fits, including the note "between 2 stars." The identity was first noticed by Pechule, and included in the Notes to IC1 by Dreyer. ===== NGC 6661 = NGC 6660, which see. ===== NGC 6666 could be any of a number of galaxies within a degree or so of Swift's position. It could also be UGC 11278 or UGC 11281 five degrees north. Whatever Edward Swift saw, it is certainly not at the position his father sent to Dreyer or later published. Bigourdan's single observation a decade after Edward Swift's is for an asterism of five stars, the brightest three in a line extending from northwest to southeast. I don't think that this is likely to be Swift's object, but it is a possibility. The asterism is 20 seconds east and 2.5 arcmin south of Swift's position, but I don't think that it would match his description. This could be easily checked, of course, with a 15-inch class telescope. ===== NGC 6667 = NGC 6668 = NGC 6678, both of which see. ===== NGC 6668 = NGC 6667 (as well as NGC 6678, which see). Found by Swift (included in his 4th list), this is most likely to be NGC 6667 as there is nothing at Swift's place resembling a "pB, pS, vE" nebula. Howe could not find it, either, and suggested that N6668 might be N6677. However, N6667 is brighter and its inner regions perhaps fit Swift's description better. Also, the difference in position is exactly 50 arcmin, suggesting a transcription error or a typo somewhere in Swift's reduction/publication chain. ===== NGC 6669 is most likely the asterism of six faint stars just north of Marth's position. This is of an appropriate size and combined magnitude that he would probably describe it as he did, "eF, pL." Wolfgang followed the LEDA group's lead in assigning this number to a 16th magnitude galaxy with a 12th magnitude star superposed well off Marth's place. Had Marth seen this object, he would certainly have mentioned the star. I think that the galaxy is faint enough, however, that the star would mask it, even at the eyepiece of Lassell's 48-inch reflector. ===== NGC 6672 is a triple star at Stephan's position. The mean position (measured on DSS) for the three stars is less than three arcseconds away from his micrometrically-measured position. ===== NGC 6677 and 6679 = IC 4763. Malcolm and I have fussed over this field for several years now, and have been unable to come to a consensus. So here is my take on the area. The two brightest galaxies here -- Malcolm's objects "A" and "B" -- were seen by Swift, Bigourdan, and Howe. (Kobold also has an observation of NGC 6677 in the Strassburg Annals, Vol. 3, 1909, but his comparison star has a high proper motion which makes the derivation of an accurate position more difficult.) I agree with Malcolm that A must be NGC 6677, but am pretty well convinced that B is NGC 6679 = IC 4763. Here's why: 1) As I always do for identification problems, I determined as accurate a position as I can for every object bearing on an identity question. In this case, this meant reducing Bigourdan's micrometric observations, and digging positions out of the Guide Star Catalogue. Here are the results for Malcolm's three objects (positions are for the equinox 1950.0): Galaxy NGC/IC RA Dec Source Notes A N6677 18 33 39.20 +67 04 09.8 GSC 18 33 38.83 +67 04 11.3 Big 5 Sept 1891 only 18 33 40 +67 04.1 Howe B N6679=I4763 18 33 33.29 +67 05 47.1 GSC 18 33 33.58 +67 05 44.8 Big 18 33 35 +67 05.7 Howe C --- 18 33 34.36 +67 06 21.8 GSC Notice that I have used Bigourdan's observations only from the night of 5 Sept 1891 for NGC 6677. His observations on 25 June 1897 refer to the star southeast of the galaxy. I also suspect that his comparison star (BD +66 1115 = GSC 4227-00549) has a relatively large proper motion as there is a systematic offset of +0.24 sec and -7.8 arcsec between his positions and the GSC positions for all the objects for which he used this star as a comparison. I've corrected his positions in the table above for these offsets. The excellent agreement between Bigourdan's, Howe's, and the GSC positions convinces me that the two micrometric observations from each of the early observers do indeed refer to Malcolm's objects A and B. Furthermore, their descriptions also make sense -- and agree with Swift's -- if we note one additional fact: object B is in fact a close double galaxy. Object C is more than 30 arcsec north of B, which puts it much too far away to be part of the object that Howe measured as NGC 6679: "This is a nebulous D * of mags 12.5, distance 5 arcsec, [position] angle 60 deg." Bigourdan's description of it as a double star, one that he could not resolve at 344X, also points to the close pair as the actual NGC 6679 -- and adds support to the evidence from his measured position that the pair is equal to Big 333 = IC 4763 (it is, of course, clear that Bigourdan himself realized this). All of this evidence, combined with Swift's own descriptions (in his papers 1, 3, and 9) seem to me to pin down the identifications without much doubt. I've not taken Swift's own positions into account as we know that they are not very good. In this case, Howe has noted that Swift's declination for N6679 in the NGC is out by 8.5 arcmin. Swift corrected this by 10 arcmin when he finally published the observation in AN 3004, but by then, the damage had been done. ===== NGC 6678 = NGC 6667 (which is also = NGC 6668, which see). IC 4762 = Big 332 is a double star at exactly the location given by Bigourdan. Until I found that it was a double star, I thought that it might be NGC 6678, found by Swift (it is No. 99 in his first list), and with an identical declination. However, I'm more inclined to believe that N6678 is the same as NGC 6667 (see NGC 6668 for more discussion); this galaxy is brighter than the double star, and its inner regions might be taken as a "pF, pS, R" nebula. Howe could not find this, either, but suggested no alternative identification for it. ===== NGC 6679 = IC 4763. See NGC 6677. ===== NGC 6682. Bigourdan was the first to notice that JH's RA is 2 minutes too large. Alister Ling picked up the error independently a century later. With an additional small correction in Dec (about 3 arcmin to the south), JH's "A large, pretty rich cluster of straggling stars ..." is found to be located in a Milky Way star cloud. The remainder of his description "... having a vacuity in the middle and broken into 2 or 3 clusters. Fills field. 70 or 80 stars of all magnitudes from 10 to 18 counted. Extended in parallel. The most compressed part following," is appropriate. ===== NGC 6688. See NGC 6693. ===== NGC 6689 = NGC 6690, which see. ===== NGC 6690 = NGC 6689. Both Swift and d'A found this galaxy twice. D'A, however, realized that his two observations referred to the same object, while Swift's second position was far enough off to mislead him into including the galaxy twice in his fifth list. Dreyer somehow recognized Swift's mistake, so only included one of the entries in NGC -- but he (Dreyer) also missed the identity with d'A's object, even though the two positions are less than an arcmin apart on the sky. Whatever happened, there is certainly only one galaxy, and it clearly bears two NGC numbers. The several descriptions are good, and all the nearby field stars are just where d'A and Swift put them in their notes. ===== NGC 6693 is lost. There are only faint stars in the area of Marth's position. The RNGC claims the object to be a star, but I see no particular single, double, or multiple star around that might have caught Marth's eye. Of the nine other objects that Marth found the same night ("1864.59"), two bracket N6693 in RA, and are at similar Dec's: N6688 and N6713. Neither has a large offset in Marth's position from the modern positions, so I have to presume that N6693 is also unaffected by any systematic error. Barring a large digit error (e.g. 1 degree, 10 minutes), Marth's object is probably gone forever. ===== NGC 6695. See IC 1294. ===== NGC 6698 may be the somewhat denser region of stars about 25 arcmin north of WH's position. If so, his position for it shares the same large offset that affects his positions for N6514 and N6533 (which see), found the same night. If this is WH's object -- his description "A suspected cluster of vF stars of considerable extent" certainly fits -- it is probably not a true cluster, but just a concentration in the rich Milky Way field. Coincidentally, the planetary nebula PK 009-10.1 is close to the center of the concentration. The proper motions would have to be checked to see if there is a connection, or indeed if there really is a cluster here. ===== NGC 6709 may also be NGC 6724, which see. ===== NGC 6713. See NGC 6693. ===== NGC 6714 is probably lost. There is nothing at Swift's position, though his note "... sev B sts nr n" is appropriate for his field. Did he perhaps see a faint comet? Since he rarely comments about verifying his nebulae, this seems a possibility worth mentioning, at least in this case. Barring a digit error, though, this object may be gone forever. ===== NGC 6717. IC 4802 (which see) is a clump of stars in this globular. ===== NGC 6724 is described by JH simply as "A cluster discovered with the 7-feet (sic) equatorial, Sept 5, 1828." He puts a plus/minus sign on the RA which he lists to only a full minute of time, though the Dec is given to his usual precision of an arcsec. About five arcmin northwest of his place is a small (5 arcmin by 3 arcmin) clump of stars, a dozen of which are bright enough to be in GSC. Given the paucity of information, though, the object could also be NGC 6709, a much richer cluster 10 minutes west at the same declination. Until further data can be dug out of JH's original observing notes (assuming there is more data), I am going to adopt the poorer clump of stars for this number -- though with a colon to flag the uncertainty inherent in the observation. ===== NGC 6726, NGC 6727, and NGC 6729 are all stars immersed in nebulae. Delisle Stewart found them associated with a much larger and fainter nebulosity, IC 4812 (which see), on a 5-hour Harvard plate. The positions I give apply to the stars. ===== NGC 6727. See NGC 6726. ===== NGC 6728 could be Isserstedt 662, a stellar ring (though it does not look very ring-like to me). This is one minute, 13 seconds preceding and 1.6 arcminutes north of WH's position at which there is nothing. WH describes the cluster as being composed of "... coarsely scattered stars, not rich." This certainly fits Iss. 662 which is the only object in the area that WH might have picked up. Those interested in Isserstedt's idea that the stellar rings have a constant size -- so can therefore be used as distance indicators -- can read more about them in A&A 9, 70, 1970 which gives other earlier references. ===== NGC 6729. See NGC 6726. ===== NGC 6731 is probably the double star whose position I give in the main table. It was found by J. G. Lohse, and is similar to other "nebulae" found by him (e.g. NGC 6344 and NGC 6767, both of which see). He describes it simply as "Very faint," though, so the identification is not as secure as it might be. ===== NGC 6735 is a clustering of stars around SAO 142915 (JH's position refers to this star), though the center of the cluster seems to be a bit southwest of the star. It matches JH's description quite well, and would probably stand out nicely in a wide-field eyepiece. ===== NGC 6737 is another of JH's clusters nearly lost against the bright Milky Way background on the modern sky surveys. His position refers to SAO 162109, though the cluster itself is centered about a minute straight east of the star. ===== NGC 6738, found by JH, is an optical alignment of a couple of dozen bright stars seen through varying amounts of dust. It is not a real cluster. Boeche et al (A&A, 406, 893, 2003) have done a thorough photometric, astrometric, and spectroscopic study of the field and have not been able to find a real cluster here. There are undoubtedly many other such clusters in the catalogues. ===== NGC 6739. There is no problem with the NGC identification, but the RC2 position for "A1903-61" points only at a star. NGC 6739 is nearby to the northwest, while a much fainter S0 is a bit closer to the northeast. I do not find this object in Sandage's southern redshift survey papers from which the RC2 references suggest it comes. Curiously, N6739 is in those papers, though three arcmin south of its correct position (probably a simple typo). ===== NGC 6743. JH describes this as "A pL, poor cl of stars forming irreg groups or patches, 11 ... 12 m; diam = 8'." About an arcminute preceding his position are three pretty bright stars and roughly 30 fainter ones scattered over an area about 8 - 10 arcmin across. This is doubtless the group that JH saw. As with many of these apparent clusterings, it may not be a real cluster. It will take astrometric and photometric studies to determine whether the stars are neighbors in space. ===== NGC 6748 may be lost forever. This is an unusual fate for one of Stephan's discoveries, as he measured all of his objects carefully with respect to stars with accurately-determined positions. He claims five measurements of this nebula with respect to SAO 86851, and describes it simply as "Pretty bright, very small, and brighter in the center." The implied offsets (for equinox 1870.0) from the star are -4m 18.53s and -9 arcmin 25.5 arcsec. Not only is there nothing at these offsets from his nominal star, I find nothing at similar offsets from other stars in the same area of sky. Unfortunately, the object is not listed in Esmiol's 1916 collection and re-reduction of Stephan's nebulae, so unless Stephan's original observing and reduction logs can be found, we will probably never recover this object. ===== NGC 6752 may also be NGC 6777, which see. ===== NGC 6762 = NGC 6763. The identity was first suggested by Howe. He apparently had a letter from Swift confirming that the two numbers apply to the same galaxy as he starts his note in MN 61, 42, 1900 by saying "These are identical; Swift admits it." Since Swift found them on different nights (30 August 1883 and 30 April 1884), and gave them virtually identical positions, there is little doubt that they indeed refer to the same galaxy. ===== NGC 6763 = NGC 6762, which see. ===== NGC 6766 = NGC 6884. Things were not looking good for this stellar planetary discovered by Pickering -- until Dave Riddle began digging around in the old literature. There he found a paper by the Reverend Thomas Espin (MNRAS 72, 150, 1911) in which Espin quotes Pickering as correcting the published position by one hour of time (20h instead of the original 19h copied into NGC). The corrected position is also the one which Pickering published in HA 60, where N6766 is tellingly out of numerical order, though without the additional NGC number (from Copeland whose position is good). Pickering's early method of finding the planetaries is interesting: he simply swept the sky looking through a low-dispersion spectrograph attached to his telescope. The stars' spectra would have appeared mostly continuous through his instrument, while the planetaries would still appear as stellar points because most of their visible light is concentrated in the emission lines of oxygen at 4958 and 5007 angstroms. Pickering later pioneered the use of objective prism photography, and several planetaries were found on Harvard plates as a result, primarily by Wilhelmina Fleming. ===== NGC 6767 is another double star found by Lohse. He describes it as "Very faint, small, round, stellar; small star near north." The double star is very close to his position, and the "small star" is 33 arcsec north. ===== NGC 6773. This is a "Coarse; not very rich, eighth class" cluster found by JH. His position refers to a pretty bright star west of the cluster's center where I place it in a 10 x 10 arcmin DSS field. ===== NGC 6774 is a large cluster, over 20 arcmin across with perhaps 75 to 100 stars as possible members. JH's position is close northeast of SAO 162395, the brightest star in (or superposed on) the cluster, but the center on the POSS1 prints is six arcmin west-northwest. ===== NGC 6775 may not be a real cluster, but it is clear on the sky as a tight clump of about a dozen stars, with another looser clump about five arcmin to the west. JH's position is on the tight clump. ===== NGC 6777 may be NGC 6752 (first suggested by Owen Gingerich in a Sky and Telescope article which appeared in the February 1960 issue on page 207). If so, there is a large error in La Caille's position. Much closer to his position is a fairly close pair of 9th magnitude stars, SAO 257685 and 257686. These were mentioned by Delisle Stewart in his Harvard Annals 60 list, and were subsequently picked up by Andris Lauberts for ESO-B. Would these two stars look like "the nucleus of a small comet" in the eyepiece of La Caille's half-inch aperture quadrant? Probably (see the discussion of a similar asterism, NGC 6634). But Gingerich's idea needs representation, too, so both objects are listed. ===== NGC 6778 = NGC 6785, which see. ===== NGC 6781. The position is for a very faint, very blue star -- the southeastern of two -- near the geometric center of the planetary. The star is not seen at all in any of the 2MASS images, but is clear on the DSS2B image. ===== NGC 6784. There are two galaxies of virtually equal magnitude and diameter here, separated by 4.6 seconds of time, and 30 arcsec -- the orientation is southwest-northeast. Which one did JH see? He has three observations of his nebula and records it as "eeF" all three times. He made only two firm measurements of its position, however (about the third, he says, "No RA observed, and the PD not to be put in competition with those of regular observations."). These are separated by 8.2 seconds and 68 seconds. Is it possible that he measured a different galaxy each time? Unfortunately, this is an unanswerable question since the orientation of his two observations is northwest-southeast. So, while it's tempting to speculate about this (and speculate I have), I don't think we can say anything definite here. Thus, I've Solomonicly attached the number NGC 6784 to both galaxies. ===== NGC 6785 = NGC 6778. JH's description reads "An eS stellar neb = a * 15m; it is 2/3 of a diam of field (= 10') from a double star which it follows, to S. Pos from the star = 240 deg +-. The RA is excessively loose." This fits N6778 if the phrase "which it follows" is changed to "which follows it." Then, the position angle agrees as well. This means, however, that not only is the RA "excessively loose," but that there is 30 arcmin error in JH's Dec as well. Bigourdan's correction to the RA quoted in the IC2 Notes applies to a random clump of stars at JH's original (incorrect) Declination. These are clearly not NGC 6785. ===== NGC 6795. The NGC description, "Cl, Ri, bet 2 sts 9", transcribed correctly from GC, doesn't really do justice to JH's original description: "The first of 3 sts 9 m, nearly in the parallel, joined by a rich clustering portion of the Milky Way." I sometimes wonder if JH wrote the GC descriptions or had a clerk do the chore for him. I've made the position a little closer to the middle of the three stars. That seems to represent the "rich clustering portion" better than JH's own place nearer the first star. ===== NGC 6797 is a triple star. Peters only gives its position and the note, "* 9m att f." The 9th magnitude star is there, but there is no nebulosity associated with the triple. Andris Lauberts was the first to identify this object correctly, in his ESO/Uppsala Catalogue. ===== NGC 6798 = IC 1300, which see. ===== NGC 6800. WH's RA is 1 minute of time too small, but JH's is correct. Since JH adopted his own position for GC, NGC also has the correct position. See NGC 6882 = NGC 6885 for more on WH's observations on the night of 10 Sept 1784. ===== NGC 6811. JH has two observations of this, separated by nearly a minute of time in RA and 6 arcmin in Dec. The RA of the first observation is correct, while the declination of the second is correct. Unfortunately, the position JH adopted for the GC carries the RA of the second, and a Dec 10 arcmin further on north. I think he meant to use only the second observation (he notes that the first observation refers to "A double star in the southern part ..."), so the incorrect Dec must be a transcription or typographical error. Once these errors are corrected, though, N6811 turns out to be quite a nice cluster, ten or twelve arcmin across, with perhaps a hundred stars, many of the 10th and 11th magnitudes. ===== NGC 6815. On POSS1, this appears to be a cluster about 20' by 10', elongated roughly in position angle 135 deg, centered about 4 arcmin southwest of JH's position. It's not too obvious on the photographs, but could well stand out while sweeping with a large telescope. ===== NGC 6816. RC3 is indeed wrong on this as it followed ESO and RNGC. SGC got the wrong galaxy, too, and as Steve Gottlieb noted earlier, JH's original description of the position of the star (six arcmin north) is correct. Looking at GC, I see that the description is exactly the same as in NGC; it does not follow the Cape of Good Hope description. So, the modification of the description is due to John Herschel himself, not Dreyer. JH must have done this to save space, though how he decided to place the star preceding as well as north is a mystery to me. He also apparently mistook the nucleus of ESO 460-G030 for one of the "vS stars" around the bright star 6' north. Herbert Howe (1898, MN 58, 515) also has a curious observation of this object: "In this is a star of mag 13.5. h noted a '* np.' I saw only a star of mag 14 at an angle of 20 degrees and a distance of 30 arcsec. The sky was dull, so that the nebula was difficult to measure." I see his "star" of mag 13.5; it looks like it is actually a superposed interacting galaxy. Howe also did not publish his position; this means that he found that the original position to be correct to within two arcmin. However, there are no stars 30 arcsec away at PA = 20. There are stars at about this PA, but they are 14 arcsec and 55 arcsec away from the nucleus of the galaxy. I wonder if Howe somehow picked up the wrong object. Well, whatever the case, while there are some unsolved mysteries here, the identification of N6816 is clear. ===== NGC 6818. See NGC 6822 = IC 4895. ===== NGC 6822 = IC 4895, which also see. The IC number is easily explained, but I am a bit puzzled at the record concerning NGC 6822 itself. William Sheehan, in his biography of Barnard "The Immortal Fire Within" has the galaxy being "swept up with the 5-inch Byrne refractor in 1884". However, in his short note on its discovery in Sidereal Messenger, Barnard says that he used the 6-inch refractor to determine its position, and that it is in the same low- power field (in the 6-inch) as the well-known planetary nebula, NGC 6818. Barnard is also a bit parsimonious with his description of the galaxy, calling it only "exceedingly faint". There is nothing about its size or shape, so the NGC description "vF, L, E, dif" probably reached Dreyer in a letter. This galaxy is important historically as it is the subject of Edwin Hubble's first published paper on Cepheids in external galaxies. Though he announced the discovery of extragalactic Cepheids in M31 in 1924, he chose NGC 6822, "a remote stellar system", as the first to have his systematic studies reported in the Astrophysical Journal (Volume 62, page 409, 1925). M33 and M31 followed in 1926 and 1929, respectively. So, extragalactic astronomy begins here, too. ===== NGC 6828 may be simply a random scattering of stars around SAO 125116 (I've adopted this star's position for the "cluster"). The GSC has a scattered concentration of about 60 stars, 12 x 10 arcmin across, centered about 2.5 arcmin southwest of the SAO star, but this does not show well on the POSS1. Perhaps it would be more outstanding visually. ===== NGC 6832 is similar in appearance to NGC 6828 (which see) -- a few dozen fainter stars are scattered around a bright "central" star, SAO 32016 in this case. However, because the background here is not dominated by the Milky Way, the cluster stands out more on the POSS1 prints and on the DSS. There are even a few galaxies seen through the cluster. ===== NGC 6837 is a cluster of about 15-20 stars 12th magnitude and fainter, only six by three arcmin in size, centered about 3 arcmin west of WH's nominal position (19 50 57, +11 34.7; B1950.0). The position in the GC and NGC comes from JH whose notes read, "Viewed. In place by working list? It is a coarse straggling part of the Milky Way." He puts plus/minus signs on both RA and NPD. It's clear that he should have used his father's position, but I suspect he thought he was. I also suspect that he did not really see the cluster that his father did as his description is not the one he uses for small clusters elsewhere in his observations. WH himself is not much more informative: "A small forming cluster of stars." He used the word "forming" literally as he interpreted the cluster as a young object just settling into clusterhood. The only real clue we have now is "small" and that fits the object pretty well. The NGC position actually lands in a region void of brighter stars. It's no wonder that RNGC lists it as non-existent. ===== NGC 6838 = M 71 may also be NGC 6839, which see -- but probably not. ===== NGC 6839. WH has one observation of this on 18 August 1784; it was the only object (not a star or double star) that he found that night. His description reads only "A very small cluster of compressed stars." There is nothing like that in the area. JH swept over the spot twice and did not positively identify the cluster either time. The position he gives for one observation is probably that reduced by CH, but he puts plus-minus signs on both coordinates. There are several small clumps of stars in the area that might be WH's object, but none stand out on POSS1, GSC, or DSS. It is barely possible that this could be M71 (NGC 6838) which is 45 seconds preceding and 53 arcmin north of WH's nominal position. Since WH recorded no other nebulae or clusters that night, we can't say anything about systematic errors without digging into the detailed records of his sweep. The offset to M71 is not unheard of in WH's observations, but it IS rare for him to have such a large position error. And M71 is hardly a "very small" cluster. ===== NGC 6840 and NGC 6843 are two sparce clusters found by JH. N6840 has two groups of seven stars (separated by about 5 arcmin) in its core, surrounded by about 5-6 others. The stars are of fairly equal brightness, all being around 11th to 12th magnitude, and cover an area of 10 arcmin by 8 arcmin. N6843 is poorer with only around a dozen stars, again 11th to 12th magnitude, scattered over a smaller area. Both are superposed on rich Milky Way backgrounds, so I'm not surprised that they did not stand out enough to be identified for RNGC. In fact, neither may be a real cluster, but proper motions and photometry could tell us that. ===== NGC 6842. Is this possibly NGC 6847 (which see)? Probably not, but it is a possibility. ===== NGC 6843. See NGC 6840. ===== NGC 6846. The RNGC position is 2 degrees too far south. At the correct position is a compact little cluster matching Stephan's description exactly: the three brightest stars are clear enough that he could see them, but the others are considerably fainter, so the entire group must have looked quite nebulous to him. ===== NGC 6847 may be the cluster and HII region 1 degree north and 30 seconds west of WH's single position. There is certainly nothing near his place, and these objects may well be the ones he saw. They are immersed in a fairly large star cloud in the Milky Way, which might have led to WH's comments about the surround area. His full description, given by Dreyer in the Collected Papers of 1912, reads, "A resolvable nebulous patch; there are great numbers of them in this neighborhood like forming nebulae; but this is the strongest of them; they are evidently congeries of small stars." Another possibility is raised by Dreyer's note in the NGC, "Not noticed by d'A, who has 2 observations of GC 5947 = m 403 [= NGC 6842, a planetary]." Is N6842 the object that WH saw? It is just 2 minutes of time preceding and 3 arcmin south of his position. There may be enough stars around the nebula to lead to WH's description, but I suspect not. Two other possibilities are nearby on the POSS prints. First is a clump of stars about 20 arcmin north of WH's position. The second is another clump about 55 arcmin south. Neither of these, however, has "great numbers" of similar clumps nearby. Dreyer notes that Bigourdan found no nebulosity at WH's place, though he searched the area four times. His one micrometric observation (I haven't reduced it) probably points at a double or multiple star. There are many of them around. Finally, using the POSS1 overlays, I thought that this might be identical to "NGC 6846" (which see). However, the overlay copies RNGC's 2 degree error in the declination for N6846 so that it lands on top of the cluster and HII region I noted at the beginning of this story. N6846 is not these objects, though as I said, N6847 might just be. ===== NGC 6861 = IC 4949, which see. ===== NGC 6873. JH's position (and so GC and NGC) is 1 minute of time too large. The correct position for Struve 2631 (the double star noted in the description) puts it into the midst of a relatively rich Milky Way field. But JH is right in calling it "... a coarse straggling group of stars 10...13m, hardly entitled to be called a cluster." The grouping is approximately 13 arcmin x 10 arcmin with a center of gravity just south of the double very close JH's position corrected by 1 minute in RA. ===== NGC 6874. WH found this on 15 Sept 1792, describing it as "A coarsly scattered cluster of large stars, of a right-angled triangular shape." This is exactly the configuration seen about 15 seconds preceding the NGC position, and is the cluster that I've taken as the NGC object. The tabulated position refers to the approximate center of the triangle. JH's position, copied correctly into GC and NGC, refers to the 10th magnitude star at the apex of the triangle, east of the center. ===== NGC 6882 is probably a duplicate observation of NGC 6885. Both clusters were found by WH on subsequent nights (9 and 10 Sept 1784; N6882 is from 10 Sept), were referred to the same star, and have almost identical descriptions: "A cluster of coarsely scattered stars." For NGC 6885, he adds, "... not rich". There is nothing striking near the position of N6882, but that for N6885 is in the middle of a large scattered cluster also observed by JH. Over the years, there has been considerable speculation about what WH saw. Some observers have made the clusters identical, while others (notably Reinmuth) have pointed at the wide group of three bright (m = 6) stars about 20 arcmin north of N6885. Brent Archinal has suggested that the clump of nine stars at 20 09 51, +26 35.1, including HD xxxxxx (the southernmost of Reinmuth's three stars), is N6882. This is unlikely as the clump is only two arcmin across. Had WH seen this, he would most likely have put it into his 7th class; it certainly is not "coarsely scattered." Neither of these matches WH's description, so I'm more inclined to the identity of the two NGC objects. This would imply an error of 15 arcmin in WH's declination; the RA's are 12 seconds different, but both are still well within the central part of the cluster (which is over 20 arcmin across). Adding to my conviction that N6882 = N6885 is the fact that, of the seven objects found by WH on 10 Sept 1784, four have significant offsets in WH's positions (the three besides N6882 are: N6800, -1 minute off in RA; N7720, +40 seconds off in RA; and N7741, +4 arcmin off in Dec). WH was clearly not up to snuff that night, and the +15 arcmin error in the declination of N6882 fits right in with the other problems. Brent has more about 20th century cataloguers' notions on the identity of these two NGC numbers in his marvelous book with Steve Hynes, "Star Clusters." I've tried to stay with to WH's observations, though, spare as they are: they are the source of the two NGC numbers, so it is primarily to them that I looked for a solution. ===== NGC 6884 = NGC 6766, which see. ===== NGC 6885 is probably also NGC 6882, which see. ===== NGC 6888 is a large oval-shaped HII region (Sharpless 105), brightest along its northeastern side. WH's place is close to the knots and streamers on that side of the nebula, and it is clear from his description that that is the part he saw. Bigourdan puts the position closer to the center of the oval. He descriptions of the field on two nights (he claims to have seen the nebula on only one of them) makes it clear that he did not see WH's object, just two stars near the revised place given in the IC2 notes. It looks like purest coincidence that this is near the center of the HII region. ===== NGC 6892 is a group of four faint stars a bit southeast of d'A's position (from a single observation). His description fits, too -- d'A suspected the object to be resolvable, but was not able to do so with his 231X eyepiece. The summary description in the NGC is an accurate assessment of how the object must appear in a moderate sized telescope at fairly high power. Also see IC 1312 for a bit more on the field around this object. ===== NGC 6895 is described by WH as "A cluster of scattered stars, above 15 arcmin diameter, pretty rich, joining to the Milky Way, or a projecting part of it." Centered close to his position (I put the center about 2 arcmin northeast) is a large cloud of stars, about 20 arcmin by 18 arcmin, most likely a random clump in the Milky Way. Four SAO stars, and dozens of fainter stars are included. This might well be a nice object telescopically, but on the POSS1 prints, it is not impressive. RNGC's "NO CL" is understandable here. ===== NGC 6896. There is only a double star at d'A's position. He has three accordant observations, and I do not see any mistake in the transcription into GC and NGC. However, d'A does talk about an RA error in his first observation. Apparently, his second and third observations a few night later revealed that error, but he gives no numbers that might suggest another position on the sky for his "cluster." With nothing else to go on, I'm left with only the double as a possibility for his object. ===== NGC 6901 = IC 5000. Seen only once by Marth, his position, correctly copied into the NGC, is off. This misled Bigourdan to measure a nearby star which he took to be N6901, and to rediscover Marth's galaxy. Thus, it got a second number, IC 5000 (which see). There is only one galaxy in the area, however, and Marth's and Bigourdan's descriptions are near enough that they undoubtedly refer to the same object. My supposition in RC2 that the galaxy is also = IC 1316 is, however, incorrect. IC 1316 (which see) was another of Bigourdan's discoveries, which he "observed" twice in different places on the same nights on which he also saw N6901. It is, in fact, non-existent. ===== NGC 6902 may also be IC 4948. See IC 4946 for the story. ===== NGC 6904 was described by JH as "A small straggling cluster of stars 10...11m. One of the 9m, whose place is taken." In spite of the inconsistency in the magnitude of the brightest star, JH's description and position is exactly correct. Wolfgang and I put the center of the cluster just southeast of the 9th magnitude star. Curiously, neither Reinmuth nor RNGC found this object. It is perfectly clear on the POSS1 and the DSS. It may not be a real cluster, but JH's object certainly exists on the sky. ===== NGC 6906 is not IC 5006, which see for the details. ===== NGC 6907. See NGC 6908 which is a superposed companion galaxy. ===== NGC 6908 is a companion of NGC 6907 superposed on its northeastern arm. Barry Madore first pointed this out to me after he examined an image from 2MASS -- N6908 is clearly a separate object interacting with N6907. It is overwhelmed on blue plates by N6907's arm, but is clearly seen not only in the 2MASS images, but on red plates as well. I suspect it would be just as clearly seen at the eyepiece of a large telescope. Marth's original description reads "eF, vS, lE (close to h. 2076)." Dreyer shortened the parenthetical comment to read "h2076 p". This is just enough different that it may have thrown both RC1 and RNGC off the trail; both noted it as identical to N6908. ===== NGC 6914 is the northern-most of three similar nebulae, probably all reflection nebulae -- the show up best on the POSS1 blue plate. Interestingly, the area on the red plate is dominated by a large HII region, centered 20-30 arcmin to the northeast of N6914. Are the reflection nebulae part of the same system of gas and dust, or are they merely superposed along the line of sight? I suspect the former, but of course can't say for sure. ===== NGC 6923 = IC 5004, which see. ===== NGC 6925 may also be IC 5015, which see. ===== NGC 6928 = IC 1325, which see. ===== NGC 6930 = IC 1326. See IC 1325 = NGC 6928. ===== NGC 6933 is usually taken as the double star centered a few arcsec northeast of Schultz's position. However, it is clear from Schultz's detailed note in his monograph that his object is actually the single southwestern star of the pair. He says of his object that it "... forms an elongated triangle with 2 stars north: star 9.5 mag preceding, star 10 mag following." His position, from 11 settings in RA and 8 in Dec on two different nights, agrees exactly with that measured on the DSS. The identification with the single star is not in doubt. Why did Schultz think it nebulous, though? His notes on the sky conditions give us clues. On 14 September 1865, his note reads, "Strong gale; images very unsteady," while on 26 August 1867, he has, "Aurora; sky first very fine, soon clouding." However, his description of the nebula itself reads, "Nebula is nearly stellar, its nebulous atmosphere scarcely perceptible; yet it looks quite differently from the surrounding stars, and has a peculiarly flickering light." By the time Schultz found this object, he was an experienced observer. His description reminds me of several of JH's descriptions of "nebulous atmospheres" around stars, stars which today show no sign at all of any accompanying nebulosity. ===== NGC 6938 is probably the scattered group of stars about a minute of time following WH's single position from 18 July 1784. There is a small core about 5 arcmin by 3 arcmin at the eastern end of a larger elongated grouping 18 arcmin by 8 arcmin -- both of these are clearly seen on the red POSS1, and both are elongated in the same position angle (about 105-110 degrees). On the blue POSS1, the small core is southeast of the center of a poorly-defined, nearly circular grouping of stars about 20 arcmin across. Even though JH saw the cluster (if that is what it is) twice, he was clearly not impressed. His first observation has no RA and only an approximate Dec. His description reads, "Very poor. The large star taken but carelessly, as it offers no interest." He did better the second time with a well-determined RA, but still only an approximate Dec, 3 arcmin south of his first estimate. He also misidentifies the cluster as "VII. 17" rather than "VIII. 17" as it properly is. ===== NGC 6950 looks like a good, if scattered, cluster on the POSS1 prints. It was seen by both WH and JH, and their positions and descriptions agree. Still, no one has included it in a cluster catalogue, and RNGC has it as not found. I suspect, though, that it could be easily dug out with a six- or eight-inch telescope. ===== NGC 6951 = NGC 6952, which see. ===== NGC 6952 = NGC 6951. Credited to Coggia, N6952 is clearly N6951 with a 20 arcmin error in its declination. The description is exactly right, and the note of a 15th magnitude star close following is also correct. Denning was apparently the first to notice the identity, but the note in IC1 gives the impression that it is the position for N6951 that is wrong. Dreyer corrects this in the IC2 Notes, but does not give a source. I suspect it is Herbert Howe's micrometric position that Dreyer is indirectly citing. I've not yet traced Coggia. Dreyer gives no clues in the introduction to the NGC, nor do I recall running across Coggia's name before. Any information would be welcomed. ===== NGC 6953 may be the group of five or six faint stars 17 seconds west of Swift's place noted by Howe and Bigourdan, and copied into the IC2 Notes. Or it may be the similar grouping of 12-15 stars three minutes of time east of Swift's position. There is no galaxy nearby. Swift found his object the same night as he found NGC 6951 (see NGC 6952 = NGC 6951 for another observation in the area), so we might expect that the same relative offsets might apply to both objects and lead us to the correct object for N6953. When we do this, however, we find that N6951 is east of Swift's position, while the sparser group of stars is west. So, I'm not even sure that the Howe/Bigourdan group is the correct identification. The number is flagged with a colon in the main table. ===== NGC 6959. This is a galaxy in the NGC 6962 group. Discovered by Lord Rosse or his observer (though incorrectly credited to Bigourdan in NGC), and measured by Bigourdan, the resulting accurate position pinpoints it exactly as object "a" in Lord Rosse's sketch. ===== NGC 6960, NGC 6974, NGC 6979, NGC 6992, NGC 6995, and IC 1340 are all part of the Veil Nebula, the wonderful supernova remnant in Cygnus. The various parts are so large, and most of them so bright, that the generally poor positions in the NGC don't matter. Only the position for NGC 6974 (which see) is completely off its intended part of the nebulosity. WH describes his "front-view" (what we now call the Herschelian focus of a reflecting telescope) in a note to his observation of NGC 6960. He writes that at the Newtonian focus the nebula extended one degree acorss the sky, while at the Herschelian focus, it stretched twice as far. He is clearly extremely pleased with the performance of his telescope in its "front-view" configuration, but I expect that the additional awkwardness in using it drove him to the Newtonian focus for most of his sweeping. In the IC2 Notes for NGC 6992, Dreyer paraphrases a short note by Pickering (at the end of an article in ApJ 23, 257, 1906) which describes the appearance of the entire Veil as seen on a 24-inch Bruce plate of 4 hours exposure. Unfortunately, Pickering chose to not publish the photograph; it would have made an impressive plate in this early ApJ paper. ===== NGC 6961. The identification is not sure. Since it is credited to Lord Rosse in the NGC, Dreyer apparently intended that the number apply to one of the five brightest objects in the N6962 group. However, Dreyer's own measurement (with Lord Rosse's telescope) on 23 August 1876 points at one of the fainter galaxies in the area. In addition, he claims that this object was found by d'Arrest, though he gives d'Arrest credit for NGC 6966 in the NGC. Micrometric positions by Bigourdan and Kobold agree with the one by Dreyer, so I've taken the measured galaxy -- located between those labeled "a" (N6959) and "d" (N6962) in Lord Rosse's diagram -- as N6961, rather than any of the brighter galaxies to the north. The evidence is contradictory, however, so I can't insist that this interpretation is correct. ===== NGC 6962 is the brightest in a group of 8-10 galaxies in Aquarius. It and the second brightest galaxy here, NGC 6964, were found by William Herschel, and remeasured by John Herschel. Of all the galaxies in the group, these two are the only ones with absolutely positive identifications. The others (N6959, N6961, N6963, N6965, N6966, N6967, I5057, I5058, and I5061) have all been misidentified at one time or another. I think that I've sorted out the mess as well as it can be, but the published record remains contradictory for a couple of the objects. See the separate discussions of the other NGC and IC numbers for more details. ===== NGC 6963 is a double star found by Bigourdan just northwest of NGC 6965 with which it is often confused. Bigourdan has two accurate measurements that point exactly to the double, and he also gives offsets to five neighboring objects in his remarks. All of these can be easily and positively identified with nearby stars or galaxies, so there is no question about this identification. ===== NGC 6964 is the second brightest galaxy in the N6962 group. See NGC 6962 for a general discussion. ===== NGC 6965 = IC 5058. This is the northern-most of the brighter galaxies in the NGC 6962 group. It was first found by Lord Rosse in 1857, and labeled "b" in his diagram. Unfortunately, it was apparently not seen again until Bigourdan went through the area a fifth time in 1891. Thus, the NGC position was apparently estimated by Dreyer from the diagram, and is not good enough to unambiguously identify the object. Bigourdan's entry under the number simply says "I can't see anything at the place indicated by Lord Rosse." He searched for it only once in August 1885. However, Bigourdan actually did see NGC 6965. It appears in his fourth list of new nebulae under the number Big 436, so received the number IC 5058. He has four measurements of it, so the position in the IC is good. That the object really is NGC 6965 could perhaps be questioned as we have only Lord Rosse's sketch to rely on. However, it is one of the brighter objects in the area, and the diagram is good enough to support the identification. ===== NGC 6966 is a double star. It is credited in the NGC to d'Arrest (incorrectly) and Bigourdan who provides an accurate position for it. d'A probably saw one of the brighter galaxies near NGC 6962 rather than this object. ===== NGC 6967. The eastern-most galaxy in the NGC 6962 group has been correctly identified by most catalogues except MCG and UGC which called it "NGC 6965." This error, combined with the correct identification in CGCG, led RC3 to include two entries for the galaxy, both, fortunately, under the correct number. See the RC3 errata paper for the correct data, which I summarize in the main table here. ===== NGC 6968 is not IC 5062, which see. Bigourdan saw and measured the two objects on the same night. ===== NGC 6973 and NGC 6980 are both stars near the NGC 6976/6977/6978 triplet. Bigourdan thought the stars slightly nebulous, so listed them among his "novae." His positions are excellent and identify the stars exactly. ===== NGC 6974 was found by the fourth earl of Rosse, and is clearly part of the Veil Nebula (see N6960 for general comments on this huge supernova remnant). However, LdR's nominal position for it falls in a pretty empty patch of sky inside the main loop, well away from any bright nebulosity. Bigourdan found no nebulosity here, either. RNGC, however, suggests that the number applies to a moderately bright patch on the northern side of the loop, southwest of NGC 6979, just a degree north of the nominal position. This is as good an idea as any about the object, but LdR's description does not match very well. LdR simply says, "Nebulous *, neby cE pf, RA = 20h 45.5m, NPD = 59d 50'+-." The part of the Veil that I've chosen has no clear star associated with it, and is not obviously extended in any particular direction, let alone east-west. I've marked the identification uncertain. Another, less likely, possibility is that N6974 is one of the 20 or so observations of NGC 6960 made with the 72-inch reflector. In this case, the position error would be in RA (5 minutes too large), and the description would have to read "cE ns." The star would be Kappa Cygni which JH took for the position of NGC 6960. I offer this as just a possibility, however; as I said, I'm inclined to think that the RNGC identification is more likely to be correct. ===== NGC 6975 = NGC 6976. Even Bigourdan, who "found" NGC 6975, admits that it is identical to N6976. Here is a free translation of his comment: "Does not exist. Because of an error of 180 degrees in the position angle estimate, Big 88 (= N6975) was thought to be new. It is identical to N6976." The RNGC is wrong. RC3 is also. ===== NGC 6976 = NGC 6975, which see. ===== NGC 6977. See NGC 6973. ===== NGC 6978. See NGC 6973. ===== NGC 6979 is a part of the Veil Nebula. WH's position for it is not particularly good, and points to a relatively faint piece of the supernova remnant. However, 7-8 arcmin to the southwest is a brighter piece that he could well have seen. I've taken this as NGC 6979. See NGC 6960 for more on the Veil. ===== NGC 6980 is a star. See NGC 6973. ===== NGC 6985. RC3 follows Skiff in placing this galaxy at 20 42 19.1 -11 17 14. This is correct, and my earlier "correction" was itself incorrect by one minute. Sorry about that (sigh). ===== NGC 6989 is listed as non-existent in RNGC. However, it seems to be a grouping in the northern reaches of the North America Nebula looking pretty much as WH saw it, "A large cluster of pretty small stars of several sizes." I put the position within a minute or two of WH's position, and make the diameter 8' by 8'. This may not, however, be a real cluster, but simply a random group of stars in the rich Milky Way field. And it may not be the object that WH saw. JH looked for his father's cluster, VIII 82, twice, once saying only "Viewed. A mere clustering portion of the Milky Way," without determining a position for it. The second night, he makes it a "Coarse, poor, pretty large cluster; stars small." He determined a position for it then, but it is 2 minutes, 15 seconds of time east, and 12.5 arcmin north of his father's position. So, when it came time to prepare the GC, he made two separate clusters out of the observations he had at hand. Since there are "clustering portions of the Milky Way" at both positions, I've kept JH's separate entries as they appear in GC and NGC. The other entry is NGC 6996, which see. NGC 6997 is a third cluster, probably a real one, in the North America Nebula. See its discussion for even more information. ===== NGC 6991. WH and JH saw two different clusters; JH mistakenly included them in GC under a single number. Dreyer, of course, followed GC for the NGC. I've included both in the table, so you get to choose which one you want. Here are the stories to help you along: WH describes his object as "A star 6 m surrounded by considerable stars forming a brilliant scattered cluster; the large star not in the middle, but following." His position is a couple of arcmin south of the bright star, but there is no mistaking the group that he saw. There is also some nebulosity on the preceding side of the cluster, but it is faint enough that neither of the Herschels saw it. JH has two observations of his cluster, which is smaller, fainter, perhaps a bit richer, and southwest of his father's. The first reads, "A star 11 m. The last of that magnitude in an irregular triangular cluster 6' diameter; poor and straggling." His second, from his next sweep, says simply, "A star 9 m; the largest of a cluster." His positions point pretty accurately to the stars he mentions, and his cluster is just as clear as his father's. But -- just as clearly -- the two clusters are not the same. Choose one if you wish. I'll take both. In October of 2005, I had the following email from Tony Flanders at Sky and Telescope: Sue French and I have been discussing NGC 6991, which she described in the October 2005 issue of Sky & Telescope (page 71). As you note on the NGC/IC website and she notes in her article, this could refer to either of two clusters, one discovered by William Herschel and one by John Herschel. There's not much doubt about JH's cluster. But I believe that the NGC/IC website has mis-identified WH's cluster. The notes (both yours and Steve Gottlieb's), together with the position and size data and the illustration at the top of the "Public Database" page, imply that WH's cluster is the concentration of stars in and around the nebulosity IC 5076. But it's hard to believe that this tiny collection of faint stars (illustrated on page 72 of Sue's article) would have been described by WH as "a brilliant scattered cluster." Sue and I both believe that Brent Archinal identified WH's cluster correctly in "Star Clusters" (pages 106 and 189) as a much larger group, about 25' in diameter, centered around 20:54.9, +47:25. As usual, it's hard to say exactly which stars are in the group, but I'm attaching a sketch of Sue's showing the "cyclops" that she describes in her article. I replied: You folks could well be right. But given the size of WH's field -- 15 arcmin -- and the magnifcation he used while sweeping -- 157X -- I think his object is more likely to be the more compact 12 arcmin x 8 arcmin cluster that is embedded in the nebulosity. My reading of his description seems to indicate this as the probable object, too (but you knew that already ... :-) However, since WH gives us no indication of size (this may also have been what threw JH off), your argument has considerable merit. If you don't mind, I'd like to quote your note above in my notes and offer it as a third choice for the NGC object. This may be one of those cases where we won't be able to reach a definite conclusion, but both interpretations should certainly be aired. Then, observers can decide for themselves. Checking Brent's note in Star Clusters, I find that he's quite adamant about his interpretation. As you might have gathered, I'm quite doubtful. So, the position he gives is in the table, but with a question mark on the identity. ===== NGC 6992 is part of the Veil Nebula. See NGC 6960 for a discussion. ===== NGC 6993 may be ESO 529-G011. Found by Leavenworth in the first seasons of observing with the 26-inch at Leander McCormick, its nominal position is particularly bad -- nearly 6 minutes of time and 13 arcmin off if the identity with the ESO galaxy is correct. Leavenworth's sketch more or less supports this notion, with the stars shown roughly in their right places with respect to the galaxy. Both the galaxy and the sketch also support his description of a small, bright nucleus surrounded by a fainter envelope. ===== NGC 6994 = M 73 is an asterism of four fairly bright stars. The Hipparcos data suggest that they are at different distances, so this is one of THE prototypical asterisms. ===== NGC 6995 is part of the Veil Nebula. The position I've chosen is more or less for the middle of the nebulous complex shown in JH's sketch, published as Figure 82 in his 1833 Slough Catalogue. He probably saw the knot we now call IC 1340 (which see) as well. Though it is off the southwest side of the sketch, the entire panel of the figure is filled with nebulosity, and I'm pretty sure that JH could have traced the nebula well beyond the boundaries he chose to include in his drawing. See NGC 6960 for more discussion of the Veil. ===== NGC 6996. This is a loose cluster, or rich region of the Milky Way, in the northern part of the North America Nebula. It has often been confused with NGC 6997 (which see) in the cluster catalogues, but the position from JH's single observation seems to be pretty good. However, JH was actually looking for his father's VIII 82, which eventually entered the catalogues as NGC 6989 (which see). As I note there, the positions that JH had when he was pulling together the GC are far enough apart that he made two different clusters out of the observations. I (1970, Griffith Observer) and Brent Archinal (1993, "non-existent" RNGC clusters monograph) present observations and further discussions of these objects. ===== NGC 6997 is a real cluster immersed in the "East Coast" part of the North America Nebula. Several of the cluster catalogues have confused it with NGC 6996, but the GC/NGC position, from a single observation by WH, is pretty good. As with NGC 6996, I (1970) and Brent (1993) have further discussions and observations. Reinmuth and Bigourdan pretty much agree with these assessments of the three clusters (N6989, N6996, and N6997) involved in the North America Nebula. And they wrote their descriptions long before Brent and I did, independently, and from different observing techniques. =====