IC 11 = NGC 281. IC 11 is one of Barnard's discoveries that he sent directly to Dreyer; it is not, so far as I know, in any of Barnard's published papers. Though included in Cederblad's catalogue of bright diffuse nebulae (and thus plotted in several atlases), it is not on the sky in Barnard's position. I have not found it on the POSS, nor on plate 89 of Barnard's own collection of comet and Milky Way photographs (Lick Publ. XI; 1913). However, the triple star mentioned in the description suggests the identity with NGC 281, and makes the RA just 30 minutes of time too small. I suspect a simple transcription error on Barnard's part. ===== IC 26 = NGC 135, which see. ===== IC 39 = NGC 178, which see. ===== IC 44 = NGC 223 is the brighter of two galaxies (N219 is the fainter). These were found by G.P. Bond at Harvard, and N223 was independently discovered by d'Arrest. The positions and descriptions are good. Swift's later description is also appropriate, especially his reference to the two stars flanking the galaxy, each about 3 arcmin away in PA's 160 deg and 340 deg. The latter of these stars is also noted by Bond in his description of NGC 219. ===== IC 45 can probably be taken as a pair of stars near Bigourdan's position. Malcolm Thomson and Steve Gottlieb have pointed out that the identification of UGC 449 as IC 45 in several modern lists, including my first guess in 1976 about its identity, is incorrect. Bigourdan's original observations support their idea. Bigourdan found the 106th and 107th of his "new nebulae" on 15 Nov 1889, but measured only the first, giving an estimated position to the second of the two. A decade later, he remeasured the first, could not find the second, but noticed a "Granulated object which could be a small cluster about 40 arcsec across" nearby. He measured the object twice that night; his reduced position is almost exactly on the brighter of two stars aligned nearly east/west and separated by about 20 arcsec. Even though his original estimated position (where he found nothing because there is nothing there!) is in the IC with the cursory description "Suspected nebula," his final list of novae has the later position with the note "Small cluster?" Thus, we take the asterism as his object even though it is not, strictly speaking, represented by the entry in the IC. ===== IC 48 = IC 1577. The position as originally published by Barnard (AN 3097; MNRAS 55, 451) is correct. In reducing the declination to 1860, however, Dreyer applied the precession with the wrong sign. This galaxy is also identical to I1577 which has an 1 min error in its RA. Barnard apparently rediscovered this after his move to Yerkes. As with so many others of his later nebulae, he sent the discovery note directly to Dreyer rather than publishing it. Barnard thought this nebula was variable: is it perhaps a Seyfert galaxy (the colors and spectrum are normal for an S0, however), or was there possibly a supernova near the nucleus? ===== IC 67 and IC 68. Bigourdan has rough measurements of IC 67 (B109) and IC 68 (B110) on 21 Nov 1889, placing them both at PA = 152 deg , 4 arcmin and 6 arcmin, respectively, from BD -7 158. On 6 Dec 1898, he puts IC 67 at the same place, but says of IC 68, "I cannot see this nebula. Perhaps it was confused with 109 Big." On the next night (7 Dec 1898), he has this to say about IC 67 (he didn't measure it then), "Pretty stellar object; I can't comment clearly on its nature." There is nothing in either of these positions on the POSS, not even faint stars. As with other similar objects, I think that -- knowing that he was in a group of nebulae -- he was pushing his eyes too hard, perhaps on a less than ideal night. ===== IC 68. See IC 67. ===== IC 71 and IC 72. For IC 71 (Big 111), Bigourdan has observations and crude measures on two nights. On 21 Nov 1889, he roughly measured an "exceedingly faint" nebula at 280 deg , 4' from BD -7 deg 159; while on 6 Dec 1898, he found a "stellar object" at 295 deg , 5' from the BD star. While the second estimate is closer to a faint star, I think that both observations must refer to that same star; there is nothing else nearby which he could have seen. I've listed the GSC position of this star in the main table. He observed IC 72 (B112) only once (21 Nov 89): "stellar object, probably nebulous" at 347 deg, 2' from the BD star. On the second night, (6 Dec 1898), he notes "Object only suspected" and gives no measures or even estimates of its position. There is a faint star at 5 deg, 1.3' from the BD star, and I suspect it is this that he saw and mistook as nebulous. However, the actual offset is rather far from his estimated place (especially the position angle), so I don't place much weight in this identification. Nevertheless, I list the star's GSC position under the IC number in the main table. There is nothing else nearby that he might have seen. ===== IC 72. See IC 71. ===== IC 77 and IC 80 are two of Javelle's galaxies in the core of Abell 151. He found both on 31 August 1892, and measured both with respect to BD -16 189. His positions are very good since the BD position for the star is within 10 arcsec of the modern position. MCG misidentified IC 80 as IC 77. This has caused some confusion in modern catalogues, though RC2 has the right IC number on the pair, calling the brighter of the two "IC 80A" (though the RC2 position is for the southern; my apologies!). That is MCG -03-04-008 which is actually northeast of MCG -03-04-009, the fainter galaxy, called "IC 80B" in RC2 (again my apologies for the wrong position in RC2). These are the two objects in the cluster with redshifts measured by Milton Humason at Mt. Wilson. Though not called IC 80 by him, his finding chart points unambiguously to them. See the HMS 1956 AJ paper for the finding chart and redshifts. ===== IC 80. MCG misidentified this as IC 77. See that for more. ===== IC 87. See IC 88. ===== IC 88 was misidentified in MCG. Unfortunately, LEDA carried the wrong galaxy along for a while. The right one is not in MCG, but is cleanly identified by Javelle's micrometric measurement. Curiously, IC 87, measured just a few minutes before IC 88, was correctly identified for MCG. Given that the IC positions are within an arcminute of the modern positions (and Javelle's when a good position is used for his reference star), the relative offset might have been a clue to IC 88's correct identification. ===== IC 89 = NGC 446, which see. ===== IC 92 = NGC 468, and IC 94. JH's NPD for N468 (correctly transcribed into the NGC) is about 4 arcmin south of the galaxy. So, when Bigourdan went over the area late in 1885 and again in 1900, he incorrectly identified a star closer to JH's position as N468. On the same nights, he found what he thought were two new nebulae in the area. One of these (IC 94) is another star, but the other (I92) is the galaxy that JH found. So, it now has entries in both catalogues. The identity was first suggested in MCG. ===== IC 93 = IC 1671, which see. ===== IC 94 is a star. See IC 92. ===== IC 97 = NGC 475, which see. ===== IC 106 = NGC 530. This "bug" arose because of bad timing. Bigourdan found the galaxy in November of 1887, just a year after Swift had first discovered it. Swift sent the discovery to Dreyer in a letter (from which it went into the NGC), then published the galaxy in his sixth list. Bigourdan also published the galaxy as a "nova" after the NGC appeared, but apparently did not realize that it was Swift's object because of the difference in RA. So, it got an IC number, too. When Bigourdan went over the area again in 1897, he had completely forgotten his earlier observation, so remeasured the galaxy with respect to the same comparison star. This second time, he recognized that the object was the same one Swift had seen and gave it its NGC number in his list. He also noted the difference in RA. Howe also caught the RA difference and published a corrected position in 1898. This appeared as a note in the second IC. Dreyer also added the identity to Howe's corrected RA. Finally, MCG suggested that the galaxy was also IC 1696, but that is a different galaxy a few arcminutes southeast found by Howe. ===== IC 107 = IC 1700 (which also see). This is the brightest of three galaxies near Swift's position. The position given by Swift -- 20 sec in error -- coincidentally falls near IC 1699, the faintest of the three. Swift, however, mentions the star 0.5 arcmin southwest, confirming the identification with the brightest. Javelle later took the brightest as a new discovery, so it received the second IC number. ===== IC 110 might be a double star, but is more likely one of Bigourdan's illusory objects, or it suffers from a misidentified comparison star. He found it the night of 5 November 1885, and based his position for it on an estimated offset from IC 111: "Mag 13.5 object situated near Big 121 [IC 111] at PA = 320 deg, distance = 0.8 arcmin; it could be a little nebulous." There is nothing in that position (there is also nothing in the place of IC 111, but that is another story, which see). About 30 arcsec northeast of the estimated place, however, is a faint double star that Bigourdan might possibly have seen. Is this IC 110? I doubt it. Since there is no trace of IC 111 at its place -- nevertheless micrometrically measured -- IC 110 is just as unlikely to be in its estimated place. The possibility still exists that it is a real star or galaxy, but I do not see a pair of objects of the right descriptions in the area offset from a star similarly bright as the nominal comparison star (BD +33 250). ===== IC 111, like IC 110 (which see), is probably lost. Bigourdan has three observations of I111 on two different nights at two different positions. His first micrometrically measured place, which is the IC position, comes from 5 November 1885, but there is nothing at all within an arcmin of that position. He describes the "object" simply: "This object could be a star accompanied by a little nebulosity." The second position, from two measurements on 19 December 1900, is about 2 arcmin away from the first in the midst of an asterism of 6 faint stars. This is not the IC position, so even though Bigourdan's description ("Slightly granulated object about 30 arcsec in diameter; it could be formed by several small dispersed stars in the guise of a pretty nebulous ensemble") and position are appropriate for the asterism, I can't really take this as the IC object. What, then, does his first observation 15 years earlier refer to? Unless he misidentified his comparison star (he calls it BD +33 250), this is one of Bigourdan's illusory objects like NGC 2529 and NGC 2531. He also claimed to have found IC 110 nearby. That, too, is missing, and I don't see a pair of objects, stars or galaxies, in the area offset from a star similar to BD +33 250 that might fit his observations. ===== IC 116. See IC 117. ===== IC 117 = NGC 560. Every now and then, I can do really silly things. When I started on this project, I did not have a good feel for the original data that went into the NGC and ICs. So, I tended to overlook obvious points that now leap off the page at me. Javelle's descriptions, for example. Dreyer called the 58th nebula in Javelle's first list "pF, S, dif, III 441 [NGC 560] sf." Well, the only object north-preceding NGC 560 is a pretty bright star. So, I took that star to be IC 117 without checking Javelle's original paper. Are pretty bright stars "pF," "S," and -- especially -- "dif" [diffuse]?" Not usually. So, 29 years later, when I ran across my note that this was a star, I looked at Javelle's original monograph to find out what's wrong. Well, Dreyer got the data copied into the IC correctly, but he apparently interpreted Javelle's footnote "On a vu les nebuleuses NGC 558, 560, 564" simply as "III 441 sf". NGC 560 would indeed be "sf" if IC 117 were at the position that Javelle says it is, but there is nothing there. The star is about 20 arcsec northeast of Javelle's position, so it is definitely not the object he measured. Re-reducing his observation does us no good as that lands within the round-off error of the correctly-copied NGC position. Did Javelle perhaps make a sign error? Nope -- there is nothing at any of the offsets implied by such an error. How about his comparison star? Well, on the night in question, he observed another nearby nebula (IC 116) using BD -2 221 as his comparison star. He claims to have used BD -2 220 for IC 117; is it possible that he used 221 instead? Actually, yes. Reducing his observation with the modern position for BD -2 221 drops his position within 2 arcsec of the nucleus of NGC 560. There is no doubt that IC 117 = NGC 560. By the way, Carlson claims in her 1940 collection of Mt. Wilson identifications that IC 117 = NGC 558. I do not know what this is based on -- the nominal position of IC 117 is closer to NGC 560 than it is to NGC 558. ===== IC 124 is a star. Javelle's micrometric position is within 6 arcsec of the modern positions, though his description "Very faint, very small, diffuse; there is a very small brilliant point in the nebulosity" does not fit the star. Perhaps he made his measurement during a spell of less than perfect seeing, or ... Fill in the dots with your own hypothesis. There are many other such objects in the IC with no explanations. The observers obviously thought they had bagged new nebulae. We shall probably never know exactly why so many of these "novae" turned out to be nothing more than single stars. ===== IC 131 is a group of HII regions immersed in two small star clouds in M33. It is often misidentified as the much brighter compact HII region about half an arcminute preceding the northern star cloud. This cannot be the IC object as Bigourdan's measurements clearly point at the star clouds, his description fits them, and he specifically mentions the compact HII region calling it a 13.5 magnitude star. ===== IC 134 is a star superposed on the northern side of M33. Though Bigourdan estimated its position on only night, and noted it as "only suspected," there are no other objects in the area that are bright enough that he could have seen. ===== IC 135, IC 136, IC 139, and IC 140. These are all HII regions or star clouds in M33. There is an error in Bigourdan's estimated offset from M33's nucleus of his comparison star for these four. He claims that the 10th magnitude comparison star is 8' south, and 31 seconds of time preceding the nucleus. There is no star that bright in that position. However, there is a star of the right brightness 8 arcmin south and 31 seconds of time following the nucleus. When Bigourdan's measured offsets for his four novae are referred to this star, the four objects can be pretty easily identified (but see IC 139!). ===== IC 136. See IC 135. ===== IC 138. See IC 1528. ===== IC 139. The identity is not quite certain. I first measured the position of a star cloud that I thought was IC 139, but this turned out to be half an arcminute north of Bigourdan's micrometric position. Checking the field, however, I found that his position is very clearly on a foreground star (or possibly a compact HII region?) of about 14th magnitude embedded in a confused area of fainter stars. His description is telling, too, as he refers to a nebula about 30 arcsec across with a brighter central point that he measured. It seems likely that the combination of the star and the background light of M33 led him to think he had found a nebula. The position I've adopted, after some consultation with Steve Gottlieb and Tony Flanders, is that of the 14th magnitude star. I've measured two or three other star clouds in the area as well and their positions are in the table, too. Also see IC 135 for a note on the identity and position of Bigourdan's comparison star. ===== IC 140. See IC 135. ===== IC 146 = NGC 648. The NGC object is one of those found at Leander McCormick soon after their 26-inch refractor went into service. The galaxy not given a good position: the nominal RA is 1.6 minutes of time too far east -- though the declination is only two arcminutes out -- and there is no surviving sketch. There are no other candidate galaxies, so the identification is pretty secure. The eastward RA error is a common one in the first two lists of nebulae found with the 26-inch. The position was corrected by Herbert Howe in one of his Monthly Notices articles. Dreyer copied Howe's corrected RA into the IC2 Notes. Unfortunately, neither Howe nor Dreyer noticed that the corrected position coincided with that of IC 146, found in September of 1892 by Javelle with the 30-inch refractor at Nice. Javelle's micrometrically measured position is good, and the IC identity is not in doubt. ===== IC 151, IC 152, IC 153, and IC 157. Four "nebulae" found by Swift for which his positions refer to nothing in the area. (The galaxy identified as IC 152 in CGCG could well be one of those seen by Swift. But the position is well off and nothing else nearby matches). A thorough examination of POSS plates E-14 and O-15 revealed no galaxies matching his descriptions or relative positions. ===== IC 152 is lost; see IC 151. ===== IC 153 is also lost. Again, see IC 151. ===== IC 155 does not exist. Found by Wolf on an early Heidelburg plate. The position has been copied correctly into the IC, and Wolf gives it three times in his short paper, so there can be no large error in his reduction or in publication. This, therefore, may be one of the earliest examples of a photographic plate defect being mistaken for a nebula. ===== IC 157. This, too, is lost; see IC 151. ===== IC 161 and IC 162. Swift's positions are again not good, but it seems likely that he saw the brightest of the three galaxies in the area in 1889, and the two brightest in 1890. Therefore, his position for the brightest (IC 161) would be 10 arcmin in error for the 1890 observation. The original IC data should read as follows: IC 161 Sw IX and X 01 41 20 80 20.4 eeF, pS, lE IC 162 Sw X 01 41 23 80 20.3 eeF, pS, R ===== IC 162. See IC 161. ===== IC 165 = NGC 684. Dreyer does not give any references in the IC2 Notes for the source of this identity. However, Steve Gottlieb has found that Isaac Roberts (in AN 3429) notes the identity on one of his early photographic plates. It's likely that Dreyer picked it up in this article. The galaxy was rediscovered, by the way, by Edward Swift, Lewis Swift's teenage son, in January 1890 while Edward was "searching for Swift's Comet." The comet was presumeably one of his father's. ===== IC 177. One of the rare cases of a rather large error in Javelle's positions. Two fainter galaxies are to the south, one of which was mistakenly identified in the MCG as I177. ===== IC 186. Javelle noted this as a double nebula, though there are actually three components -- the eastern galaxy is itself a close double. There is a much fainter compact galaxy south of the western component, but Javelle could not have seen it with the Nice 30-inch. ===== IC 187 and IC 188. Though large errors exist in Swift's places for these two galaxies, they could have been seen by him, and the descriptions are not inconsistent. ===== IC 188. See IC 187. ===== IC 191 = NGC 794. Swift's position is just nine seconds preceding JH's (adopted for GC and NGC), close enough that Dreyer suggested the identification in the IC. The descriptions are quite different, however, suggesting that Swift picked up the galaxy on a particularly good night, while WH and JH must have seen it on poor nights, or when their speculum mirrors needed repolishing. In any case, the identity is almost certain as there are no other galaxies nearby that the Herschel's or Swift could have seen. ===== IC 198. See IC 199. ===== IC 199 = IC 1778. When the same galaxy is discovered twice by the same observer, it is usually by one whose positions are not very good (e.g. Lewis Swift has quite a few objects in his lists that he "discovered" more than once). It is rather unusual that Javelle, who measured everything he found micrometrically, should list the same object as new in two different lists. Yet that is what he has done. When his observations are reduced, they fall within about a dozen seconds of each other, and both point unmistakeably to the same galaxy. Even more curiously, on the second night (29 Jan 1897), he noted that he also remeasured another of his "novae," IC 198, from the first night (15 Dec 1892). Yet he did not recognize that his observations of the object in question were in fact for the same object. Curious indeed, but there it is. ===== IC 200. The galaxy 34s following the IC position is probably too faint to have been seen by Safford, and the description does not match in any case. The object 2 minutes of time following does match his description, and a 2 min digit error is more likely to be made than a 34s error. See IC 1008, IC 1026, and IC 1030 for other notes on nebulae found by Safford with the Clark 18.5-inch that also share digit errors in their RA's. ===== IC 206 and IC 207. The positions were referred to the wrong star by Javelle. The relative positions are exact, and the descriptions match. I209 (whose place in Javelle's list is correct), referred to what Javelle supposed to be the same star, was found and measured one night later than I206 and I207. ===== IC 207. See IC 206. ===== IC 209. See IC 206. ===== IC 210. See IC 1528. ===== IC 217 = IC 1787, which see. ===== IC 225 may also be NGC 867, which see. ===== IC 228 = NGC 944, which see. ===== IC 229. A nebula is marked on the CD chart, and Dreyer read its position correctly from the chart -- but it does not, in fact, exist. Since Thome was observing with a small telescope (12.5 cm), it is unlikely that he saw and incorrectly recorded any of the fainter galaxies in the area. Unlike the other four "nebulae" found by Thome (IC 1023, 1203, 1207, and 1290), this one is not an asterism, either. The nebula is not on the 1929 edition of the CD charts, so may have been an error affecting only the first edition. ===== IC 233 has been misidentified as the fainter, southern galaxy of a pair, most recently by LEDA and NED. It is, of course, the northern, brighter object. That has the star south 1 arcmin, too, just as Javelle noted. ===== IC 240 is probably a line of four faint stars. The IC position is correctly copied from Bigourdan's second list of novae in Comptes Rendus, but his detailed observations suggest that he applied his estimated offsets to the comparison star with the wrong signs. In that case, the position would be about an arcmin southeast of NGC 996; there is nothing there. However, this observation is in Bigourdan's list of errata. There we find that the data in the big table is reversed from its true values: "In place of PA = 30 deg, read 210 deg and change the signs of delta RA and delta Dec." When this is done, we can recover the IC position, and find that it falls near the line of stars. I'm still curious about his description in Comptes Rendus: "Mag. 13.3; 35-40 arcsec." His description in the observation list reads only "eF, only suspected." Where did the size come from? (There are several other such discrepancies among his published novae.) In this case, there is no supplemental observation, so the source of his size estimate remains a mystery. In any case, it's clear that Bigourdan was not much interested in his "novae," and preferred to spend his time measuring the brighter, well-known nebulae. ===== IC 242 is one of a double star. Javelle's position is not good enough to tell us which one, and his description, "eF, eS; nearly in contact with a very small star," does not give us relative positions, either. But it looks as though the proximity of the two stars misled him to seeing nebulosity where there is none. IC 243, found the same night, and less than 3 arcmin to the northeast, is well-measured with respect to the same comparison star, so there is no possibility of a mistaken comparison star for IC 242. ===== IC 243. See IC 242. ===== IC 249 = NGC 1051 = NGC 961. In spite of Javelle's assertion that IC 249 is "distinct from NGC 1051" (he says nothing about the relative orientations; that is Dreyer's interpretation for IC1), his measured position shows that it is the same object as the one that Stephan saw (and later Stone; his RA is 10 minutes off, leading to the number N961 for his observation). Here are the precise positions: RA (1950.0) Dec Notes Stephan 02 38 34.63 -07 08 52.0 (Re-reduced wrt GSC pos for comp *) (NGC 35 08.9) Javelle 02 38 33.57 -07 08 56.2 (Ditto) Bigourdan 02 38 34.07 -07 09 03.5 (Ditto; one delta dec rej). Skiff 02 38 34.15 -07 08 59.9 GSC 02 38 34.01 -07 08 57.5 n = 2 HC 02 38 34.1 -07 09 00 Sup * GSC 02 38 35.69 -07 08 33.7 n = 2 Notice that Stephan's position is about 1.05 seconds (16 arcsec) following Javelle's, though the declinations agree to within the errors. One possible source of the large difference is proper motion of the comparison stars. This could be significant since each of the visual observers used only one comparison star each (each used a different star). However, Stephan's comparison star (BD -7 490 = Weisse 678) is almost 1.5 degrees away from the galaxy, while Javelle's and Bigourdan's are about 5-6 arcmin distant. Therefore, I'm inclined to give a lower weight to Stephan's position for NGC 1051 than to Javelle's or Bigourdan's. It's also possible, of course, that one or the other of them simply made a 1 second of time error somewhere in their reduction or transcription to the publication. However, when Javelle made his measurement, Stephan's was the only other micrometric observation, so Javelle probably assumed that it was correct. This might lead him to believe that the difference (21 arcsec) between St's RA (as given in NGC) and his own is significant. The difference is coincidentally close to the RA difference (25 arcsec) in the GSC between the galaxy and the superposed star north following. If Javelle saw the star with even the slightest haze, he could well have thought that it was the real NGC 1051, since it is considerably brighter than the galaxy. Thus, he would have listed the galaxy as a "new" object even though it is clearly the same one that Stephan and Stone saw. The similar descriptions from all the observers, including Steve Gottlieb's, also point to their having seen the same object. Unfortunately, as was his custom, Javelle did not mention the superposed star. ===== IC 256. This identification is now (March 2005) fairly secure. The object I've picked for IC 256 is very faint, and I'm surprised that Swift could see it. However, Steve Gottlieb reports a solid detection with his 17.5-inch reflector, so it is conceiveable that Swift could indeed have picked it up with 16-inch refractor. This particular galaxy falls out almost by default if the two brighter objects Swift found nearby -- on the same night -- get the numbers IC 257 and IC 260. Swift's absolute positions for those two are not too bad, but his descriptions help only with I260 -- he has it "in line with 2 nr F sts"; the stars are there. He notes his other two objects as being "in [a] vacancy." This isn't quite true as this is a low-latitude field rich in faint stars, but there are no eye-catchingly bright stars near the galaxies. Finally, there is nothing at his position for I256 except I257. I had earlier posed the question "Is this another case where an observer picked up the same galaxy twice on the same night?" Well, maybe, but it's doubtful. In any event, I'm going to take this galaxy as IC 256 on the basis of Steve's observation. The galaxy, by the way, is either a double galaxy, nearly completely merged, or a galaxy with a faint star superposed just 4-5 arcsec north of the nucleus. None of the images I've seen are completely clear about the nature of the northern object, at least without detailed photometry and/or spectroscopy. ===== IC 257. See IC 256. ===== IC 258 and IC 259. Burnham gives his original observations and reductions for these two nebulae in Lick Obs. Publ., II, 181, 1894. All his measurements and computations are correct, but his final position for "Neb. II." (= IC 259) is 30 seconds of time in error. ===== IC 259. See IC 258. ===== IC 260. See IC 256. ===== IC 261 = NGC 1120, which see. ===== IC 263 and IC 264. Javelle misidentified his comparison star. Malcolm Thomson found the correct one: BD -0deg 436 (Javelle incorrectly claimed -0deg 438). When this change is made, CGCG 389-027 clearly becomes IC 263, with Javelle's re-reduced position falling within 2 arcsec of the nucleus. IC 264, however, is subject to yet another error: Javelle's printed RA offset has the wrong sign. When changed to the correct minus sign, I264 is shown to be a faint, otherwise uncatalogued galaxy matching Javelle's description. As with I263, his re-reduced position is within 2 arcsec of the nucleus. ===== IC 264. See IC 263. ===== IC 274. There is nothing much near Swift's position. About 7 arcmin northeast is a galaxy that he might have seen, however. And 3 arcmin east is a small group of stars (a double and a triple) that could also be the object he saw. Unfortunately, he does not tell us anything about the star field, so neither of these is a very solid identification. ===== IC 275 is a triple galaxy close to Swift's position. It's possible that his object is only one of the three, and that the "F star near preceding" is a second. There are also two candidates for his "D star nr sp", the prime one being a wide double about 3 arcmin southwest. ===== IC 280 may be no more than an asterism of 4 faint stars. There are no galaxies or nebulae within 10 arcmin of Swift's position, and his description is scanty enough to make the stars a likely candidate. Also, Swift's positions for the other four objects found that night are pretty good, aside from a -1 minute error in the RA of IC 282 (which see). ===== IC 281 = NGC 1177. This is a clear case of oversight on Dreyer's part, as well as Swift's. The positions are very close, and the descriptions are also very similar. Dreyer himself made a measurement of N1177 with Lord Rosse's 72-inch, so it surprises me a bit that he did not check Swift's observation more closely with the NGC. Whatever happened, the identity is sure. See NGC 1177 for more on this field. ===== IC 282 = NGC 1198. Swift's RA is just -1 minute of time out. Otherwise, the position is good, and his description fits. ===== IC 286 is lost, though perhaps not permanently. Bigourdan found it while searching for NGC 1202 (which see, and which is about 24 seconds of time preceding Ormond Stone's discovery position for it), but gave it only an estimated offset from a star at 03 01 54, -06 39 (1950). Unfortunately, there is no star at that nominal position. Bigourdan notes the star at 43 seconds preceding and half an arcminute south of a star he called BD -7 545. This is 10 seconds following Bigourdan's nominal position, and there is still nothing there. I also checked at 43 seconds following the BD star -- nothing. In his description of NGC 1202 (which he claims to have seen, but did not measure because of its faintness), Bigourdan describes the field around the BD star: "It [NGC 1202] is situated at PA = 175 deg, d = 2.5-3 arcmin with respect to the star BD -7 545. This star, magnitude 9.0, has a companion 12-12.5 toward PA = 125 deg, distance 1 arcmin." This precise description of the field does not match what we see on the sky around the star, so I am almost certain that Bigourdan misidentified some other star as the BD star. A search for several degrees around BD -7 545 fails to turn up any other star of similar brightness with companions in the relative places Bigourdan gives. So, I've been unable so far to recover the objects which he took for NGC 1202 and IC 286. My earlier conjecture that IC 286 = NGC 1202 was based purely on the fact that Bigourdan's nominal position for I286 is 15 seconds of time away from NGC 1202. Given the problems with the comparison stars, that conjecture is clearly wrong. There are couple of things still to check. For example, did Bigourdan by mistake look at BD +7 545, or BD -7 454? Until we've covered those possibilities, it may be premature to declare IC 286 "Not found." By the way, IC 286 is not NGC 1202 as I supposed in ESGC. Bigourdan saw the two of them, or thought he did, on the same night, 14 December 1890. ===== IC 290 = IC 1884. IC 290 was found near Algol by Swift on 11 September 1888 along with several other galaxies. His positions are not particularly good, so Barnard thought that he discovered the group when he was working in the area sometime later. He did not publish his observations, but sent them directly to Dreyer. Fortunately, his positions are good in this case, so we don't need to appeal to the original observations for verification. The other galaxies involved are IC 1883 = NGC 1213 (also found by Swift, but in October of 1884), I292 = I1887, I293 = I1888, and I294 = I1889. I295 and I296 are also supposed to be in the area, but are not. See them for some speculation. ===== IC 292 = IC 1887, IC 293 = IC 1888, and IC 294 = IC 1889. As I noted above for IC 290 = IC 1884, Swift's positions for most of these are poor enough that Barnard was misled into thinking that he had discovered a new group of nebulae near Algol. Also see NGC 1213 = IC 1883 (the fifth galaxy in the group) for more. (Swift has two additional nebulae here, IC 295 and IC 296, neither of which exist. See their brief notes, too.) ===== IC 293 = IC 1888. See IC 290 and IC 292. ===== IC 294 = IC 1889. See IC 290 and IC 292. ===== IC 295 is probably lost. It is supposed to be in a group of nebulae found by Swift near Algol (see IC 290 for more). In particular, it was found on 11 September 1888, the same night as I292-294. But there is no trace of it in the area, and Barnard found only five galaxies here when he went over it later, while Swift claims a total of seven (N1213, I290, and I292-296). ===== IC 296 may be a reobservation of IC 294; it was found three nights later on 14 September 1888. See IC 295 for more. ===== IC 297 is probably one of the two double stars that I've listed in the table. Swift found it on 15 Sept 1888, and called it "eeeF, pS, R; 4 sts in line s; F * p close sp [sic]; eee dif." Swift's note as printed is not very clear about the star to the west or southwest. Dreyer took it to mean southwest. The line of four stars is unmistakeable at 03 09 48, +41 52.0 (1950), but there are two candidate double stars to the north. The eastern of the two doubles more or less matches Swift's note with a faint star to the southwest, while the western double has TWO stars southwest and one southeast. So, while that western double is brighter, the field matches the eastern better. There are, by the way, no galaxies in the area with stars matching Swift's note. In particular, the line of four stars is just where Swift places it with respect to his nominal position -- but there is no galaxy there. My earlier guess at the identification was a much fainter double star much closer to Swift's position. But this double, I recognize now (Feb 2005) is much too faint for Swift to have seen. You can see it yourself, though, on the DSS at 03 09 58.5, +41 55 37 (1950). ===== IC 300. Swift's position is OK, but his description should read "bet 2 sts 9, np and sf" instead of "* 9 sp." Am I seeing the same object that he did? If not, there is a large error in his position, and we need to keep looking for his object. ===== IC 314 = NGC 1289. Bigourdan notes in his big table, "This nebula, 11 sec following the position given in the NGC, was published as new (140 Big.)." The identify with N1289 is therefore certain. ===== IC 319 is a star. There is a faint galaxy 45 arcsec south preceding that has been mistaken (by me, among others) as IC 319. However, Bigourdan's two micrometric measures of his nova (= Big 141) point precisely at the star. Furthermore, his description of the surrounding star field is exactly matched if the star is his reference object -- but not if the galaxy is the reference object. Malcolm Thomson has also pointed out that the galaxy is probably too faint to have been seen by Bigourdan. In fact, there is another galaxy near a wide double star that Bigourdan measured in this field. This second galaxy is brighter and larger than the first, and Bigourdan makes no mention of the second. I presume that he did not see it, either. ===== IC 323 is a triple star very close to Swift's position. He notes this as the "preceding of 2", the second being a rediscovery of NGC 1334 (not included in the IC by Dreyer). Swift's position for that is very good, too, so the identity of I323 with the star is pretty sure. ===== IC 324 = NGC 1331 which is the fainter of two nebulae here discovered by WH (the brighter is N1332). His place for N1331 is poor, however, and falls coincidentally near a vF wisp that he could not have seen. The RNGC unfortunately identifies the wisp as N1331=I324. The galaxy that Herschel actually saw was correctly measured at Leander McCormick and by Bigourdan, though Bigourdan did not accept the identify with N1331 and published the galaxy as new (142 Big.). Dreyer (M.N. 73, 37, 1912) makes the identity clear, but recommends dropping the number N1331 in favor of I324. However, since the NGC number has been in general use for many years (e.g., in the Mt. Wilson and Helwan lists, in RC1 and 2, etc.), I have retained it here. ===== IC 333 does not exist. It was only suspected by Bigourdan, and observed by him just once. There is nothing in his measured position east-southeast of N1358 (which he also saw), so this, like IC 67 and IC 68, was probably an illusion. ===== IC 335 = IC 1963, which see. ===== IC 336, IC 341, IC 353, IC 354, and IC 360. These eF diffuse nebulae were identified by reference to Barnard's drawing in A.N. 3253, and to his drawing and photograph in M.N. 57, 12, 1897. Barnard's sketch is more or less confirmed by PSS plates O and E441 and O and E31. Curiously, Dreyer did not include all of the patches of nebulosity shown by Barnard, and those that he did list in the IC are not necessarily the brightest. With the possible exceptions of I353 and I354, these nebulae are probably not associated with the Pleiades, but appear more likely to be Galactic reflecting nebulae (see Alan Sandage's article in AJ 81, 954, 1976 for more on these fascinating objects). Note also that the IC position of I360 is 5m in error. ===== IC 337. Swift's position does not match anything in the area. The object in the table is certainly bright enough to have been picked up by Swift, but its position is well off in both RA and Dec. MCG -01-10-009 is about 1.2 minutes preceding the nominal position, and only a couple of arcmin off in Dec, but it has such a low surface brightness that I doubt that Swift could have seen it. Also, he mentions that the galaxy forms a "trapezium with three stars." None of the galaxies in the area fit this description. So, yet another mystery. ===== IC 341. See IC 336. ===== IC 346. See IC 2090. ===== IC 348 = IC 1985, which see. Dreyer put this into the first IC apparently without seeing Safford's footnote which reads, "A loose cluster with nebula." All that appears in the IC description is Safford's "vL, vgbM, pB" rearranged into the usual brightness-size-concentration order. Whatever happened, Safford is right -- there is a cluster associated with this nebulosity. Barnard did not mention the cluster, either, in his discovery note for IC 1985, though he examined the object both photographically and visually with the Yerkes 40-inch. ===== IC 349 is a knot in the Merope nebula less than 40 arcsec away from the star. For many years, I had thought it equal to NGC 1435 (which see), but that is the much larger and fainter nebulosity stretching 10 to 15 arcmin south of Merope. Like the larger nebula, I349 is a reflection nebula. It is, in fact, the brightest of the nebulosity around the Pleiades. In his discovery note in AN 3018, Barnard has micrometric measurements of IC 349 with respect to Merope. It is from those that I have reduced the position given in the table. The bright glare around Merope is so intense that IC 349 is difficult to photograph. Nevertheless, it's been done with some regularity over the years. Herbig has the full story in AJ 111, 1241, 1996 (with a follow up with Theodore Simon in AJ 121, 3138, 2001). When I was observing regularly, I didn't know enough to look for I349 as a "separate" object, or I might have done so. It will certainly be challenging for any observer who does go after it! ===== IC 353. See IC 336. ===== IC 354. See IC 336. ===== IC 359. The 1m error in Swift's RA has led to considerable confusion concerning the identity of this object. The diffuse nebula referred to by Lynds and Cederblad is about 1/2 a degree northeast of the IC object, and Hubble's (Ap. J. 56, 400, 1922) questioned identification is also incorrect. ===== IC 360. See IC 336. ===== IC 371 is a star. Bigourdan also mistook another nearby star to be NGC 1586 (d'Arrest's position quoted in the NGC is bad). Bigourdan's micrometrically measured positions (from 2 nights) are exact and refer unambiguously to the stars. ===== IC 376 is a fainter galaxy about 1.5 arcmin northwest of IC 377, which see. It is mentioned, though not identified, in the MCG note for I377. ===== IC 377. MCG has labeled this "IC 376-7". Unfortunately, only the first -- incorrect -- number has stuck on the galaxy. That number actually belongs to the fainter companion 1.5 arcmin to the northwest, while only I377 applies to MCG -02-12-031. ===== IC 382. This may possibly be NGC 1632, but that is more likely identical to IC 386, which see. ===== IC 386 is probably = NGC 1632. Note the possible confusion here over the identity of N1632 -- its quoted position falls between IC 382 and IC 386. The RNGC (probably incorrectly) chooses I382, the larger and brighter galaxy, as N1632, but does not mentioned the IC number. The NGC position, however, is closer to I386 and the descriptions (through similar size refractors) are the same. So, somewhat cautiously, I am going to adopt that identity. ===== IC 394 does not exist. Observed only once near N1667 by Bigourdan and noted as "Suspected only. It's existence is not at all certain." There is, indeed, nothing in the area. ===== IC 395 may also be NGC 1671, which see for more. ===== IC 397. Observed twice by Spitaler, but there is only an eF * near his position that he could not have seen. Another case of a misidentified comparison star, perhaps? ===== IC 400. Stone measured only the RA of this object, so the IC NPD is marked uncertain. In principle, the RA ought to be very good, as it was measured four times using a chronometer. Unfortunately, there is nothing at the derived RA anywhere near the nominal declination. Two seconds following, there is a faint late-type spindle, though it does not match the sparse description (m = 16.0, diameter = 0.1 arcmin) well. I also have my doubts whether the spindle could be seen visually, even with the 26-inch: its surface brightness is pretty low. There is also a transcription error in the Leander-McCormick list. The comparison star is called "CCO 228" at "04 55 03.54, -15 55 03.3" for 1890.0. Checking through the table, I noticed that CCO 228's declination is given differently in the observation for NGC 1730 (obs. no. 208): "-15 57 47.3". The declination of CCO 225 (in another observation of N1730, No. 203) is the same as that for the declination given for the comparison star of IC 400 (obs. no. 209), while the RA is different. So, which star did Stone use as a comparison for his new nebula? Since he used CCO 225 (which is SAO 150054) only for the one observation of N1730 on a different night than he found IC 400, it is most likely that the correct star is CCO 228 (SAO 150066). This makes the RA of the spindle close to the measured RA -- but it is still far enough off to bother me. Is there significant proper motion for the star? Perhaps it has moved enough in the interval between early 1889 when Stone observed it, and 1950 -- the SAO epoch and equinox -- that it could account for the difference in RA. The spindle has a faint companion about 20 arcsec southwest with a brighter star superposed. Is it possible that the combined image is actually Stone's object? It would be closer to his position than the spindle, but still a full second of time off. At the moment, I'm not willing to say which object -- if either -- is IC 400. There are just too many puzzles here. ===== IC 410 is a nebulosity found by Max Wolf in which is embedded the cluster NGC 1893, found by JH. While Wolf noted stars in his nebula, JH apparently did not see the nebula at all. Therefore, the common practice of equating the two objects is incorrect. This was pointed out by Brent in "Star Clusters" and by Wolfgang in an email. I've fixed the position tables accordingly. ===== IC 411. Swift noticed two other nebulae in the area of IC 411, but did not measure their positions. The two galaxies listed near IC 411 are the brightest in the area next to 411 itself, and may possibly by Swift's nebulae. ===== IC 412 = IC 2123 and IC 413 = IC 2124 were discovered by Javelle and also by Barnard -- twice. While Javelle published his observations, Barnard apparently sent his directly to Dreyer. The positions and descriptions are close enough that one or the other of them should have become suspicious about the identities. But that was left until the CGCG folks ran across these fifty years later. Different words describe this same situation under IC 2123. If curiosity overwhelms you, go see that number. ===== IC 413 = IC 2124. See IC 412 = IC 2123. ===== IC 419, IC 425, and IC 439 were all found by Wolf on a Heidelberg plate. IC 419 is only a line of 4 stars about 1' long (and matches Wolf's description in this respect). IC 425 and IC 439 are probably defects on the Heidelberg plate as no nebulae matching Wolf's descriptions are in this area of the sky. ===== IC 422 = IC 2131, which see. ===== IC 425 does not exist. See IC 419. ===== IC 429, a small cometary nebula found by Javelle, is indeed involved in IC 430 as supposed by Dreyer. Javelle actually saw and measured only the "head" of the nebula, while the fainter "tail" stretches off about an arcminute to the southeast. This is reasonable, recalling that Javelle was observing with a 30-inch F-23 refractor. Modern identifications of this nebula include PP37, V883 Ori, and Haro 4-13a (my thanks to Dave Riddle for this information). It is part of the star formation complex around the Orion Nebula (M 42 = NGC 1976). IC 430, discovered photographically by Wilhelmina Fleming on two of four plates covering the region of the Orion Nebula and reported by Pickering in Harvard Annals XX, No. 6, 1890, is just where Fleming puts it. This is the nebula that Wolfgang originally listed under the number IC 429. ===== IC 430. See IC 429. ===== IC 439 does not exist. See IC 419. ===== IC 443 and IC 444. I'm not quite certain which parts of these nebulae, apparently along nearly the same line of sight by coincidence, are meant to carry the IC numbers. Wolf makes clear in his article that the positions he gives (only to a full minute of time and a full degree) are quite crude, so I have assumed that he means to include all of the nebulosity. On the other hand, Dreyer adopted Barnard's (unpublished? If in print, I've not found the paper) descriptions and, at least for IC 444, position. These seem to suggest that Barnard saw only parts of the objects on his early plates. However, until I can find Barnard's descriptions, I'm hesitant to try to tag just parts of these nebulae. Still, I attempted to do that when I first looked at these in Scotland in the mid-1970's. Those positions are still in the table. But after Wolfgang asked about the identifications early in 2003, I estimated positions for the entire extent of the objects. Those are in the table, too. ===== IC 444. See IC 443. ===== IC 446 = IC 2167, which see. ===== IC 447 = IC 2169, which see. Also note that this is not NGC 2245 (which see) in spite of Barnard's note in the Lick Publications, Vol 11, Plate 28. ===== IC 452 = NGC 2296, and IC 453. Bigourdan has N2296 = B148; this is wrong. N2296 = B147 = I452. His relative positions for the two objects and their neighboring stars are precise, and B148 = I453 is unambiguously a star. Bigourdan's position as published in Observations, Vol. I is correct, though the IC position is 8' in error. Though NGC 2296 looks something like a galaxy, it is probably a small diffuse nebula. It is in a starless patch southeast of Sirius, and Clemens and Barvainis, ApJS 68, 257, 1988 have a detection in CO giving a radial velocity of +16.6 km/sec. This almost certainly confirms the Galactic nature of the object. ===== IC 453. See IC 452. ===== IC 457 may be (or maybe not!) NGC 2330, which see. ===== IC 458 may be -- but is probably not -- NGC 2334. See NGC 2330 for a discussion. ===== IC 459. See NGC 2330. ===== IC 462 is a star. It has a faint galaxy nearby that may have helped give the impression of nebulosity to the star. This is the only one of Kobold's nine new nebulae in the area which is not a galaxy. For more on this group, see the extensive discussion under NGC 2330. ===== IC 465 may be NGC 2334 (or, as with IC 457 and NGC 2330, maybe not!). See NGC 2330 for a discussion. ===== IC 468 is a triple star. Bigourdan has two observations, but his second applies to another star 14 seconds west of the double. ===== IC 470 is probably a double star near Swift's position; there are no nebulae in this area. The double is about the right brightness to have been mistaken by him on a poor night as a tiny nebula. He found only one other nebula on the same night (2 October 1891), IC 1300 (which see). That has an error of exactly one degree in its position (it is = NGC 6798), but there are no nebulae a degree north of the nominal place of IC 470. At least Swift did not make the same mistake twice on the same night. ===== IC 487 = NGC 2494, which see. ===== IC 488 may be the star with the accompanying faint, compact galaxy that Wolfgang has chosen. But Rudolf Spitaler's very precise position, measured with respect to two different comparison stars on the same night (8 Feb 1891), is over 20 arcseconds away. His two measurements, reduced with respect to the AC2000.2 positions for the comparison stars (epoch 1902.43, close enough to Spitaler's observation date that I've ignored the eleven plus years of proper motion), are accordant to within two arcseconds. I had originally thought that his object was the triple star on to the east of the double, but that is even further from his measured place. All the candidate stars for IC 488 are listed in the position tables. Another mystery: In his description of his nebula, Spitaler mentions a 13th magnitude star 16.84 seconds preceding, 20.4 arcsec south of his nebula. That star was 15.74 seconds west and 34.4 seconds south of the double (for equinox 1891.11). But reducing his offsets with respect to the AC2000.2 position (epoch 1903.35) for the star leads to a position 1.88 seconds of time on east and 30.9 seconds south of his other two positions. So, his three measurements are not internally consistent. For the time being, I've listed the star+compact as the most likely candidate, but am not convinced that either it or the triple was Spitaler's object. In addition, he calls it a quarter of an arcminute in diameter. While the distance across the triple is about 20 arcseconds, the separation of the star and galaxy is only 4.6 arcsec. The other obvious option is a comet. But this seems unlikely as Spitaler's three measurements are not internally consistent and I think he would have noticed a comet's motion against the background stars (unless it was very distant, of course). So, I suspect some sort of errors in his observations, but cannot even guess what they might be. I also should note that I mistook the compact galaxy for a star when I first saw it (my previous note calls the pair a double star). But having loaded the SDSS into NED, and revisiting the IC objects a couple of months later, I found that the SDSS team had actually taken a spectrum of the galaxy and found it to have a redshift of z = 0.1919 (57,530 km/s). This is one of the largest redshifts for any object in the IC, and makes it less likely -- in my mind, at least -- that Spitaler actually could have seen it. The SDSS g-band magnitude is around 18, probably too faint for the galaxy to have been picked up even with Spitaler's 27-inch refractor. Perhaps the galaxy added a bit of fuzz to the nearby star, but I'd want to check it in a similar-sized telescope. ===== IC 489 is a star. Spitaler describes it as "A small (not more than 10 arcsec diameter) faint nebula with a stellar nucleus." His single micrometrically- measured position used BD +26 1704 as a comparison. At the time he published the measurement, he had no good position for the BD star, so his roughly reduced position is the one that appears in IC1. A few years later (see "Wiener Annalen XI, 125"), he got a good position for the BD star, so was able to properly reduce his measurement. Dreyer provided a more accurate NPD in the IC2 Notes that leads us directly to the faint star that Spitaler mistook as a nebula. ===== IC 496 = IC 2229. This and IC 2229 are almost certainly identical. Both were found by Javelle; while the mean of his micrometric positions agrees to within a few seconds of the GSC position, he does not mention the existence of a nearby second nebula in either observation (one made 2 March 1892, the second 11 Feb 1896, with both being referred to the same star) -- unless one interprets his remark "extended east-west" as including the following object (both galaxies are extended north-south on the PSS). The 2nd is actually an interacting double system. Both of its components are fainter than the one single brighter galaxy 15 arcsec preceding. ===== IC 501. Included as a new nebula by Wolf in his first "Nebel-liste" from Heidelberg Bruce plates, Dreyer caught the identity with the IC1 object and did not assign it an IC2 number. ===== IC 507 = NGC 2590. The IC position is 12.5' northeast of N2590. However, Dreyer made an error of about 30s in reducing Swift's RA to 1860. When correctly reduced, the RA for I507 is identical to that for N2590, and the declinations are 10 arcmin different. Since Swift's description is similar to Stephan's for N2590, the identity seems certain. ===== IC 511. See IC 895. ===== IC 518. Not found, though observed twice (six years apart, first in 1890) by Bigourdan near N2618. His micrometric observations are in agreement and are unambiguously referred to BD +1 2137. However, there are only a few vF stars near his place, and nothing at all that matches his description. The RA given in the IC, though correctly copied from the Comptes Rendus paper, is wrong: it should read "08 28 51." ===== IC 532 apparently does not exist. Bigourdan normally gives detailed observations of the nebulae he observed. However, among those that he discovered, seven (IC 532, 543, 759, 1164, 1206, 4977, and 5303; see the notes for each of the others for details specific to them) were listed only in the two tables in his Appendix VII devoted to his new nebulae. They also appear, of course, in his separately published lists of new nebulae from which Dreyer extracted them for the NGC and IC's. No differential positions from nearby stars are given for these seven objects in Bigourdan's main tables, so we have only his reduced positions and the published descriptions to go on as we attempt to identify them. IC 532 = B 152 is especially curious among this group, as it was apparently the only object that Bigourdan recorded twice (23 and 25 March 1887). In addition to the position and date, we have a magnitude ("11?") and the remark "Fausse image?" as well as the IC description, "pB, pL, Epf, bM." The object was not found at Helwan in the 1920's, and I found no trace of it on the PSS while working on ESGC. Was it possibly a comet as was IC 2120, and perhaps IC 4977? Or was it, as Bigourdan remarked, simply a "false image"? ===== IC 538 = NGC 2885, which see. ===== IC 541. There is a faint star near Swift's place that he might have seen as an "eeF, pS, R" nebula -- but there is no sign of the "10m * s" that he mentions in the description. There must be a large error in Swift's position, but a search of the surrounding area turned up no galaxies that he might have seen with a 10th magnitude star to the south. ===== IC 543. The MCG has this = NGC 2902, but as Bigourdan observed the NGC object in its correct position, B.155 = IC 543 is not likely to be the NGC object. There is a faint galaxy 4.0 arcmin southwest of NGC 2902 that might be IC 543, but Bigourdan's positions are usually better. There is also a star near the position Bigourdan lists, but -- as with IC 532 (which see) -- he gives no details of his observation, so we have only his position and description ("vF, pL, E, dif") as clues. Neither supports the notion that Bigourdan actually recorded the star (unless the seeing was extraordinarily bad that night). One curious note: this object, IC 532, and IC 759 all come from the night of 23 March 1887. Perhaps the seeing was bad. Or did Bigourdan misplace his original observations? ===== IC 547 = NGC 2947 = IC 2494. The RA of N2947 is 2m 14s in error, but the NPD is good, and the descriptions (given the different telescopes used) match. Swift's position is fair, and Howe missed the identity with I547 (as did Dreyer), so the object received an entry in IC2 as well. It is, so far as I know now (May 2003), the only object to have an entry in all three of Dreyer's catalogues. ===== IC 554 = IC 555. Though there is a fainter galaxy near the nominal position for IC 555 (at 09 40 12.3 +12 36 44, B1950.0), it is more likely that Swift saw the same brighter object that Javelle did and made a 10 arcmin error in the declination. ===== IC 555 = IC 554, which see. ===== IC 556 = NGC 2984. The position for N2984 is poor, but as it was observed by both W. and J. Herschel, there can be little doubt as to its existence. The RNGC accepts Reinmuth's questioned identity (N2984 = I556), and I see no reason not to do the same. Javelle's position is good. There is a faint star 0.5 arcmin south-southwest, and I556 is the brightest in a group. ===== IC 565 has a very compact companion very nearly superposed on its warped disk. I've mistaken this companion as a star at least twice, but it is clearly non-stellar on closer inspection, even on the DSS image. ===== IC 573 = NGC 3058s. The NGC position is again off in RA (but note Howe's correction in an IC2 note), but the description is accurate as is the NPD. Javelle could not have been aware of Howe's correction which was published after Javelle's first list. Javelle's place is good, but his "vS * close" must be N3058n. ===== IC 579 may be MCG -02-26-005, but the MCG galaxy is 23 arcmin north of Swift's nominal position. The RA's are identical to within Swift's usual (rather large) error, which makes this the only reasonable candidate near Swift's position. However, it is fainter than I'd expect for an object that Swift describes as "pF, pS, R" (unfortunately, he has nothing about the star field). I have not yet checked for digit errors in the position. Perhaps Swift's Dec is one degree or ten degrees off. Or maybe his RA is ... (and so on). This should be checked before pronouncing the MCG galaxy as certainly being the object Swift dug out. ===== IC 580 = NGC 3069. Discovered by Dreyer with LdR's 72-inch, this is pretty well-placed by him at 5 arcmin north-northwest of NGC 3070. He does comment, however, "Clouds," which would account for his remaining caution in describing the object: "... an object which I have little doubt is a vF, vS neb, perhaps lE". Though the NGC position is a little over an arcmin southeast of the galaxy, there is no doubt that it was seen by Dreyer. Why, then, did Javelle think it was a "nova"? That he made some mistake is clear since he claims, in a footnote to IC 584, that I584 is "Distinct from NGC 3069 and 3070." Which two of the galaxies in the area he thought were the NGC pair is not clear to me, though. In any event, Javelle's position for the galaxy makes clear that he saw the same object as did Dreyer; the identity is secure. ===== IC 585 is a companion to NGC 3080, which see for more information on Bigourdan's observations. ===== IC 591, creditted in the IC to Javelle, was also seen by David Todd during his search for "the trans-Neptunian planet" in 1877. It is Todd's number (22). See NGC 3604 for more. ===== IC 604 = NGC 3220. Swift's description and position pinpoint NGC 3220 as the correct object. He most likely simply did not check the NGC before publishing this as new, as the NGC position -- from WH -- is good, too. ===== IC 606 = NGC 3217, which see. ===== IC 617 is the brightest of the triplet NGC 3280 = NGC 3295 (which see for another story). Neither NGC position is very good, so Javelle can be excused for thinking he had a new nebula. I do find it a little curious that he did not mention the two slightly fainter galaxies just following the brighter one that he measured. He was, after all, using a 30-inch refractor, larger than the 26-inch that Leavenworth used to sketch the triplet. There is, in any case, no doubting the identification. Javelle's micrometric measurement falls within a few arcseconds of the nucleus of the brightest galaxy. ===== IC 618 = NGC 3296, which see. As with IC 617, also found by Javelle, the NGC RA (from Leavenworth) is so far off that Javelle did not notice the identity. That was left to Herbert Howe. ===== IC 619 is UGC 05735. Swift's description of the three stars following the galaxy was summarized by Dreyer in IC1. In full, it reads: "A p l (sic) triangle of 3 F sts nr f, one a vF D." The "vF D" is indeed one of the stars southeast of the galaxy. A somewhat fainter star follows the double by 2.5 arcmin, and turns Swift's stars into an even more striking asterism. Swift's position is therefore off by +19 seconds and -20.0 arcmin. ===== IC 620 is the brighter of a double galaxy. Unfortunately, CGCG put the IC number on its entry for both objects, so the number has migrated to the fainter galaxy in its journey to LEDA (as of July 2004; it should be fixed soon). Javelle's position is good, and falls within four arcsec of the brighter galaxy. ===== IC 621. The IC position is about 2.5 arcmin too far north because the BD position for Javelle's comparison star (BD +3 2388) is in error by that amount. When the correct position for the star (from PPM, SAO, or GSC) is used, IC 621 is clearly identical with CGCG 037-074, not with CGCG 037-075 as claimed in CGCG. ===== IC 622 = NGC 3279, which see. ===== IC 625 is ESO 501- G080 = MCG -04-26-001. Muller's RA offset from NGC 3335 has the wrong sign in the big 1893 Leander McCormick list of micrometric observations. Rather than being 3min 3.6sec west of N3335, it is that distance east. The description fits, including the position angle, and there is no doubt about the identity. ===== IC 629 = NGC 3312. This is the identity that Bigourdan published in his big table without comment. So, we can only speculate as to why he thought he had a new nebula when he first went over the field. Perhaps it was JH's slightly uncertain north polar distance. In his first observation of it on 26 March 1835, he says "... PD only correct to the nearest minute." His polar distance is not, however, marked uncertain. But in his second observation four nights later, he says "No PD taken, a hurried observation, and the wire mistaken ([RA] rectified in reduction)." Curiously, his single polar distance is two arcminutes south of that in the NGC (which is just an arcminute south of the modern position for the galaxy). No other observers are creditted with observing this, so either Dreyer or JH made a mistake in transcribing the NPD into the GC and/or NGC, or JH has other observations that his did not include in his CGH volume. In any event, Bigourdan's object is certainly the same as JH's and the identity is sure. ===== IC 640 and IC 641 do not exist. Though Bigourdan has micrometric measurements for both of them -- four for IC 640 -- on 27 March 1887, he notes, in italics, "This is, without doubt, a false image" for both objects. The nominal positions are both near bright stars, about 15 arcmin apart. There are several galaxies in the area, but only NGC 3381 -- for which Bigourdan has separate measurements -- is bright enough to have been seen by him. I'm going to trust his comments and call both objects non-existent. ===== IC 641 does not exist. See IC 640. ===== IC 644 = NGC 3398, which see. ===== IC 646. See NGC 3398 = IC 644. ===== IC 652 = NGC 3421. Even though these numbers refer to the same galaxy, the nominal positions are 25 arcmin apart on the sky. Common's position for the NGC number is 13.5 arcmin too far north (and is actually a mean position for this and its companion, NGC 3422), while Javelle's is 11.5 arcmin too far south. Common's position is a crude estimate from his setting circles, while Javelle's is, like all of his, micrometrically measured. Unfortunately, as he sometimes did, Javelle misidentified his comparison star. Rather than being BD -11 2960 as he claims, it is actually -11 2959. Once the right star is used for the reduction, Javelle's position falls within five arcsec of the nucleus of the galaxy. The identity is certain. ===== IC 656 is a triple star with a very faint galaxy just south of the eastern-most star. Found by Bigourdan, he later claimed it to be identical to NGC 3460 (not true; see N3460 for more). There has been additional confusion over the identification of this, since it is possible that this was actually the object seen by JH and the "Mr. Bailey" mentioned in JH's description. It is also possible that d'A saw this object when he was looking for h793. See both NGC 3457 and NGC 3460 for more. In any event, the IC identification is secure; Bigourdan's position, from five measurements on two nights, is within a few arcsec of the triple, and his description is appropriate. ===== IC 669, creditted in the IC to Javelle, was also seen by David Todd during his search for "the trans-Neptunian planet" in 1877. It is Todd's number (8). See NGC 3604 for more. ===== IC 670. See NGC 3531. ===== IC 675 may be the double star listed in the main table. There is certainly nothing at Javelle's position, and there is no error in his data for his nominal comparison star, BD +4 2426. His offsets (+46.78 seconds, -2' 29.6"), though, are matched (+46.43 seconds, -1' 28.8") -- except for the error of 1 arcmin in Dec -- by the double and a 12th magnitude star that he might have used as a comparison star. That star, though, is fainter than almost all his other comparison stars. Still, the double star matches his description, and the agreement of the offsets (that pesky 1 arcmin aside) make it tempting to accept the double as IC 675. Were it not for the fact that Javelle mentions NGC 3580 in a footnote, I might suggest that it is IC 675. But there is no star at any reasonable position that might have been the comparison star that Javelle used. In the end, we have a possible identification, but no more. ===== IC 682 = NGC 3649. Swift's RA is one minute of time too small, and I think that his note "vF * close np" applies to NGC 3646 -- there is no star northwest of NGC 3649 that he could have seen. Otherwise, his observation fits NGC 3649 very well. I assume typos and/or transcription errors. ===== IC 683. See IC 684 and NGC 3645. ===== IC 684 = NGC 3644. Even though Marth's positions, adopted in NGC, for NGC 3643, 44, and 47 are good, Bigourdan misidentified the latter two objects. He placed N3644 some 35 arcsec south-following his position for IC 683 (which has a 1 arcmin error in Bigourdan's big table in the distance from the comparison star, and he measured a star as N3647) -- there is nothing in his measured place. He lists two "new" objects in the area, I683 and I684. His positions for both are good, and that for I684 is almost identical to Marth's position for N3644. Also see the discussion under NGC 3645. ===== IC 688 was found by Ormond Stone in January 1888. He measured it micrometrically (12 settings in RA, 2 in Dec), as did Frank Muller about a year later (12 RA settings, 4 Dec settings). They referred their two sets of measurements to the same star, and it is those that I've used to re-reduce the position. (Stone has another set of four measurements using another star, but he did only the RA; I've not reduced these, but they are consistent with the other measurements.) The position so reduced is within a couple of arcseconds of the 2MASS position, so there is no question about the identity of the galaxy. Unfortunately, Wolfgang picked up a fainter galaxy 44 seconds of time further on east and called it IC 688. I did not catch this until I was loading the IC into NED early in 2005, so all my earlier lists have the wrong galaxy. ===== IC 689 = NGC 3661. The IC number is from another of the Leander McCormick micrometrically measured nebulae that found its way into IC1 by mistake. The two positions -- NGC and IC -- are virtually identical, yet neither the LM observers (Muller and Stone) nor Dreyer noticed this. This is even more puzzling since Muller and Stone did notice the NGC number on the following of the two nebulae, NGC 3667. Oh, well -- these things happen. Just to add to the confusion, Stone misidentified his comparison star, though Muller did not. Had the LM folks reduced their observations to RA and Dec, they probably would have noticed this. The stars, by the way, are two of three in a line southwest of the galaxy. Though of approximately equal brightness, only two of them made it into the BD extension. Stone thought his star was the first of the two BD stars, but it was actually the one the BD observers missed. ===== IC 694 is the faint galaxy just northwest of the peculiar interacting pair NGC 3690. Swift's discovery note is not very clear about the object's location with respect to the NGC object, but his position places it northwest. If we assume that he took the NGC position for 3690 and offset from that to find his own position and compare the offsets with those from the modern positions, we find roughly the same numbers. Swift, however, was not the first to see IC 694. Lord Rosse's observation of NGC 3690 in 1860 mentions an "appendage" about one object (i.e. NGC 3690) diameter northwest. This description fits what he could have easily seen with his 72-inch "Leviathan," so Dreyer correctly credits him as well as Swift with the discovery. ===== IC 696 is the largest of a group of galaxies including IC 698 and IC 699. All these, and many others, were seen on an early plate taken by Max Wolf at Heidelberg in the early 1900's. Many of the "nebulae" that Wolf found are, in fact, stars near the plate limit. See IC 2849 for more about these early plates. ===== IC 698. See IC 696. ===== IC 699. See IC 696. ===== IC 700. This is a compact group of galaxies, Hickson 54. Javelle may have seen just the largest and brightest of the objects. However, his description, "Nearly round, about 40 arcsec in diameter, a little brighter toward the middle," suggests that he saw at least the brightest three of the objects, blended into a single image. His estimated size easily encompasses at least these three, and perhaps all four. I've included all of the galaxies in the table. ===== IC 703 and IC 704 are a pair described by Swift as "eeF, S, R, p of 2" and "eF, vS (? close D), f of 2". His positions orient them southwest/northeast and separated by about 4 arcmin. There is nothing in the area that matches these constraints. There is a possibility that they may be NGC 3704 and N3707, about 1m 40s west of Swift's nominal positions. But those are on an almost exact east-west line, and are separated by only about an arcmin. Also, the brighter object is the western, while Swift makes the eastern brighter. Finally, NGC 3707 shows no sign of being double. There is also the possibility that NPM1G -11.0302, about 4 arcmin north- northeast might be the second of Swift's nebulae, with N3704 the first. Again, however, the Lick galaxy shows no sign of duplicity, and it is even fainter than N3707 and is thus less likely to have been picked up visually. The only other nebulae that Swift found on the same night (IC 619 and IC 799) have problems of their own (I619 is 20 arcmin north of Swift's position, while I799 is identical to NGC 4520). So, a systematic error in Swift's positions can't be claimed for the night. All in all, there is not much to go on here. So, the identifications with the NGC objects are only tentative, and very questionable. ===== IC 704. See IC 703. ===== IC 713 may be a 17th magnitude star near Bigourdan's estimated place. He notes the object as "only suspected", so he may actually have glimpsed the star. But it is so faint, that I wonder if he actually did, especially given that it is just 3 arcmin north-northeast of a 7th magnitude star. ===== IC 714 = NGC 3763, which see. ===== IC 717 = NGC 3779, which also see. Frank Muller observed this and NGC 3775 before the NGC was published, so the "name" he assigns to NGC 3775 is the reference to Common's short list of new nebulae in Copernicus. He also used NGC 3775 as the reference "star" for his observation of this. Given that he knew about Common's list, I find it a little odd that he labels this galaxy a "Nova" in his list. Unfortunately, Muller measured only an RA for the galaxy, and that is exactly 30 seconds of time too large. His offset from NGC 3775 is printed as +0min 53.92sec. Since he measured this three times, I suspect this is a simple transcription or typographical error somewhere between his observing log and the published table. Whatever happened, Muller's description leaves no doubt that he saw NGC 3779. He called it magnitude 15.8, diameter 1.0 x 0.8 arcmin, extended 90 degrees, diffuse. This is perfect for this low surface brightness object, so the identity with N3779 is certain. ===== IC 722 and IC 724. Spitaler misidentified his comparison star, and gave it the coordinates of yet another misidentified star. The star he actually used is BD +09d 2534. He claims he used BD +09d 2531, and gave the coordinates of BD +09d 2532. His descriptions of his objects, however, leaves no doubt as to the correct identifications. He notes a "* 10 nf 2 arcmin" for I722, and "lE 45d" for I724. Both clearly identify his objects; they are both 8 seconds east and 5.5 arcmin south of his positions (which Dreyer copied correctly into the IC). ===== IC 724. See IC 722. ===== IC 726. Spitaler's declination offset has the wrong sign in his paper: it should be "+" rather than "-". This puts Spitaler's position exactly on a faint, otherwise uncatalogued galaxy. Curiously, there is a somewhat brighter galaxy (UGC 06696) just two arcmin to the northwest. How did Spitaler miss that? Well, it's a busy field (see NGC 3847, NGC 3855, and IC 2953 for more). ===== IC 730 = NGC 3849, which see. ===== IC 732. There are two galaxies at Bigourdan's place, roughly the same size and magnitude. Which one did he see? Going into his big table, we find that his description reads "Extremely faint and diffuse, but its existence is certain; I can see brighter points in it which may be stars 13.4-13.5." So, he saw both objects, even if marginally. ===== IC 734 is double, though Javelle's description is for a single object. Reducing his micrometric position, we find that he measured, and presumeably only saw, the southern object. ===== IC 735. There is nothing in the IC position. But going into Javelle's first paper, we find a footnote on page B.32 that reads "Page B.13, nebula no. 202, in place of 79d 0.6m, read 76d 0.6m." He caught a typo, apparently in proof before the final printing plates for the second section of his paper were set. When we make that change, Javelle's position falls exactly on UGC 6775, and his description fits the galaxy. ===== IC 736 and IC 737 are the two brightest galaxies in Hickson 59. They have been misidentified in several catalogues (including CGCG and Hickson's) in spite of the relatively good positions given in IC. Javelle discovered them on the same night and measured them with respect to the same star. Re- reducing his positions with respect to the AC 2000.2 position for that star removes all doubt about which galaxies he saw. ===== IC 739. Javelle misidentified his comparison star. Though he claimed it to be BD +24 2401, it is actually +24 2403. When we re-reduce his observation using the correct star, his position falls within a few arcsec of the modern data for UGC 06830. ===== IC 740 = NGC 3913, which see. ===== IC 755 = NGC 4019, which see. ===== IC 757 = NGC 4068. Bigourdan misread his micrometer so that his position angle is 180 degrees out -- his "new" object is southeast of his comparison star, not northwest. Curiously, he made the same mistake on two objects -- the star that he mistook for NGC 4068 as well as his "nova" -- on two nights. His observations on a third night were interrupted by a storm. While he was preparing the manuscript of his big table for publication, he noticed the mistaken position angles and commented that the observations as recorded in his log book would be impossible at the declination of the objects. Once the correction is made, his position ends up within a few arcsec of a star superposed on NGC 4068, and his description ("Uncertain traces of nebulosity to one side of a * 12: the nebulosity follows this star."). This same star marks the position given for the galaxy in several more recent lists, too. The center of the outer isophotes of the low-surface-brightness dwarf galaxy is about 10 arcsec northeast of the star. A few arcsec further on is a faint knot or, perhaps, the nucleus. ===== IC 759 has to be marked "not found." This is another of only seven of Bigourdan's new objects for which he provides no details in his big tables of differential positions (see IC 532 for a general note on these objects). The only information we have comes from his Appendix VII in his Introductory volume, his second list of new nebulae published in Comptes rendus, and the first IC, which Dreyer, of course, took from the Comptes rendus list. The NGC description reads "pB, pL, Epf." In Appendix VII, we also find that the magnitude is 12.7, and a remark, "Fausse image?" Added to this is the information that Bigourdan apparently found this while observing NGC 4086 -- but he provides no differential positions for that object, either. So, the possibilities come down to these: 1) Was this perhaps a false image caused by a reflection from SAO 082124 (at about the same declination)? 2) is the object actually NGC 4086? or 3) is it the faint galaxy at 12 02 41.9, +20 35 21 (B1950.0). None of these seem particularly likely. Finally, to finish with a curious "coincidence," Bigourdan dates this discovery to 23 March 1887, the same evening on which he found IC 532 and IC 543 (which see). Bad seeing, maybe? Lost observing book? There are any number of possibilities. ===== IC 765 may be the star 10-12 arcsec southeast of Bigourdan's position. He has only one observation of the object, using NGC 4152 as the comparison object. Oddly, his position for N4152 in his big table is nearly 6 arcmin off, but the position for I765 in his list of novae is correct. Dreyer also copied it correctly into IC1 -- but there is still nothing there. Carlson has this as a double star. I suspect that the second star is the one an arcmin or so further southeast. But this is too wide to have been mistaken for a nebula by Bigourdan, and since he says nothing about stars near his nebula, I suspect that both stars are just a bit too faint to have been seen by him. In any event, I've put the first star in my position list as a possibility, but think that IC 765, too, is "not found." ===== IC 772 = IC 3067. Bigourdan's coarsely reduced position in IC1 was not good enough to alert Javelle 15 years later -- or Dreyer five years after that -- that the nebula had already been found. Also, Javelle's north polar distance offset has the wrong sign, throwing his position off the galaxy, too, and even further from Bigourdan's position. Hence, two IC numbers. There are also two other galaxies nearby that might confuse the identification problems for these two numbers were it not for the fact that both observers nailed the object to within five arcseconds when their observations are reduced using Tycho-2 data for their comparison stars. There is no doubt about the identity. ===== IC 778 = NGC 4198. Swift's position is exactly 5 minutes of time too large. Otherwise, his observation matches N4198 very well. Curiously, however, he notes that the star to the north is 13th magnitude, while the star south of the galaxy is the brighter of the two. Did he confuse his directions as well as the RA? I'd have thought that an observer would call special attention to the brighter of a pair of stars rather than the fainter. ===== IC 788 = NGC 4405. This identity was first suggested at Harvard, probably by Frost or Ames during their work on the Virgo Cluster. That it is, in fact, correct is shown when Javelle's observation is carefully reduced -- the resulting position lands exactly on N4405. Javelle also makes no mention of the NGC galaxy in his list, but does say in a footnote, "Distinct from the nebula which carries the no. 21 in the 7th Catalogue of M. L. Swift." That 21st nebula is IC 787. So, the note in the IC "II 88 [N4405] south" is almost certainly Dreyer's based only on the relative positions that he had in front of him. In any case, the identity was adopted in CGCG and MCG, so has found its way into the modern catalogues. ===== IC 793 = NGC 4445. IC 793 is the only nebula that Swift found on 6 May 1888. His description, "eF, S, eE; 3 others in field", was adopted almost unchanged by Dreyer for the first IC, so offers no clues beyond what we have in the IC itself. Swift's position precedes N4445 by about 15 seconds of time, and his description suggests that he certainly saw the same galaxy as d'Arrest. My guess is that Swift did not have either the NGC or d'Arrest's monograph in hand when he prepared his 8th list for AN, so he really did believe that the nebula was a "nova." Since the galaxy is in a moderately rich part of the Virgo Cluster, Swift's other three nebulae are probably also nearby NGC galaxies, most likely N4424, N4442, and N4451. If Swift did not have d'Arrest's monograph, I'm a bit surprised that he did not include N4424 and N4451 in his 8th list, given that neither was recorded by the Herschel's. Perhaps (pure speculation) he was clouded out before he could estimate positions for them. ===== IC 799 = NGC 4520. WH's position precedes the galaxy, while Swift's follows it; this probably accounts for Swift's belief that he found a new nebula. Both observers noted stars involved with or close to the galaxy. WH probably mistook the nucleus as one star and picked up the one just to the west as his second, while Swift suspected only that western star. ===== IC 802 is a star. Bigourdan saw it only one night when he was trying to find NGC 4572 (which see). His observation under that number also refers to a star, just about as far south of the galaxy as this star is north. In his description, he notes (a free translation), "It could well be only a star." He's right. ===== IC 805 = NGC 4611. Neither Swift nor Dreyer recognized the identity even though Swift's position is only 9 seconds west and 0.5 arcmin north of Stephan's. Perhaps the different notes about neighboring stars (Stephan: "... between two very faint stars." Swift: "... two pB stars north and north-following." Both notes are correct, by the way.) misled both astronomers. Stephan also notes that the galaxy is "... a little extended southeast-northwest," while Swift simply has "round." In any event, the two numbers apply to the same galaxy. ===== IC 808 is only two neighboring stars mistaken by Bigourdan for a slightly nebulous cluster. The galaxy identified by Wolf in his sixth list of nebulae as IC 808 is much too faint for Bigourdan to have seen. Wolf's position and comment "* 11 s 1 arcmin" clearly identify his object, just as Bigourdan's position points exactly at the following (slightly brighter) of the two stars. ===== IC 811 = NGC 4663. Bigourdan found the galaxy in 1888, too late for inclusion in the NGC, but it did make IC1. It's position there is different enough from Tempel's estimated one for N4663 that Dreyer included it without hesitation. Turning to Bigourdan's big tables, though, we find entries for both numbers. That for IC 811 has just two measurements on 13 May 1888. The mean offsets are +19.19 seconds in RA, and -7 arcmin 01.2 arcsec from a star identified as "A.G. Wien-Ott. 4631" which has an accurate and precisely given position. On 8 May eight years later, he has four measurements for NGC 4663. The mean values are +19.15 seconds in RA, and -7 arcmin 01.7 arcsec from the same star. Bigourdan has no notes about the two observations being for the same galaxy. I suspect the reason that he did not notice this is that the data are on successive pages of the table. I also suspect that Bigourdan did not prepare all the data for publication himself, but had help from one or more of the several people hired as "computers" at the Paris Observatory. They would have churned through the numbers as quickly as possible. Even if they had noticed the identical measurements, they may not have mentioned them. In any event, the NGC position is a bit off. Dreyer cobbled it up from Tempel's discovery note, which (roughly translated by me) reads, "About 8 arcmin south following NGC 4658 is a small, very faint (WH class III) nebula; it itself precedes a star 13-14 mag; a measure by me with the ring micrometer came to nothing." (I presume that the galaxy was too faint for him to measure accurately.) The galaxy is actually 7.2 arcmin south-southeast of N4658. This puts the nominal position far enough off that Bigourdan, taking it literally, found nothing where he was expecting it. However, just a few arcmin away just happened to be this small, faint nebula ... The identity was apparently first noticed by the Mt. Wilson observers, and was copied into RC1 and MCG from there. ===== IC 815 is not IC 3760, though some lists -- notably Adelaide Ames's Virgo Cluster catalogue of 1930 -- equate them. Frost has both objects in his list, and places them about 1.5 arcmin apart. His positions, however, are given with a precision of only an arcminute. So, the actual separation, just over an arcminute, is well within his nominal error, and the two galaxies are clearly separate objects. GSC includes them both, and I've listed them as separate objects in my tables. ===== IC 816. See IC 817 = IC 3764. ===== IC 817 = IC 3764. Schwassmann's position is accurate, and -- surprisingly -- so is Swift's. This hasn't prevented confusion in the area, though, as IC 816 is close preceding (and a bit south; Swift's notes have the relative positions flipped north to south -- IC 817 is "nf of 2", not "sf"). Ames has incorrectly equated IC 816 with IC 3764. I wonder if Swift has mixed up his notes on IC 816 and 817. I817 is the fainter galaxy, and has the wide double star only 4 arcmin northwest. Yet Swift calls I816 the fainter of the pair and mentions the star in its description. And there is the nf/sf switch, too. So, I wonder ... ===== IC 823 is probably the star about 1.5 arcmin southwest of NGC 4692. In his list published in Contes Rendues, Bigourdan says "Suspected near NGC 4692 at p = 220 deg, d = 1.5'", a comment that Dreyer changed to "Susp, 2' s of II 381" for the IC. Unfortunately, there is a star in both places, so the southern one was chosen by Wolfgang, and -- in an earlier attempt at finding this object -- by me. However, Bigourdan's reduced position, from a single observation in 1885, is about 2 arcmin to the southwest of the galaxy, and falls on an empty patch of sky. The star he probably glimpsed is 20 arcsec directly north. His description from his big table "Suspected only; could be nebulous" is similar to that for other stars he found, so I've adopted the star -- with a cautionary colon -- as IC 823. ===== IC 824 = NGC 4678. Here the fault lies with the NGC position from the second Leander McCormick list -- the RA is 3 minutes of time off. Otherwise the description pretty well matches, including the "* f 2s." Javelle's position (re-reduced with respect to the Tycho-2 position for his comparison star) is very good, and he apparently had a better view of the galaxy than did Frank Leavenworth. Javelle noted that the galaxy was extended east-west, and that it has at least two bright "nuclei." Leavenworth even questions its nebular character. Given the chronically poor positions from Leander McCormick, I don't doubt that the two catalogue numbers refer to the same galaxy. ===== IC 825. This is probably the object picked up 95 years after Swift's observation as IRAS F12477-0505. Swift's position is not too bad, and his description ("eeeF, pS, R; nearly bet 2 sts east and west; 2nd of 3; [NGC] 4705 and 4718 near") is appropriate -- except for the "nearly bet 2 sts" phrase. This does not match the IRAS galaxy (a peculiar double or triple system) which has a star only to the east. It does, however, fit NGC 4718 perfectly. Is it possible that Swift confused his observing notes between the two objects? Or is it possible that his "nova" is actually NGC 4718 itself? If so, the mystery phrase becomes "2nd of 3" as N4718 is the third of the trio, not the second. Occam's Razor: take the IRAS galaxy, but include the identity with N4718 as a questionable possibility. ===== IC 829 is in the core of Abell 1631, and is one of the brightest galaxies in the cluster. Unfortunately, it is misidentified in MCG, and therefore in PGC as well. Bigourdan's offsets clearly point at the following galaxy of a close pair, while MCG chose a third galaxy 5.5 seconds of time following. ===== IC 833. The skeptic in me has been overly active of late. Here's a case: the galaxy that is obvious to take as IC 833 is within an arcminute of Swift's position, and is a dead ringer for his description, "vF, S, R". On the face of it, there is no problem at all. However, just five arcmin south of the faint, little galaxy that is so "obviously" the one that Swift saw, there is another nearly 2.5 magnitudes brighter, NGC 4813. Swift makes no mention of this in his very brief description, yet this would have been an outstanding object in his 32-arcmin field were it centered on the fainter galaxy. As Malcolm has pointed out, a five-arcminute separation often appears elsewhere in Swift's observations described as "near" or "close". So, I wonder, is NGC 4813 actually the object that Swift saw? But that's all I can really do -- wonder. What there is to go on, the entry in Swift's 8th list, points directly at the little guy. Maybe Swift really did see it, and I'm just being stroppy. But maybe, just maybe ... So, I've sprinkled some colons and question marks around. ===== IC 834. Dreyer has a note in the 2nd IC indicating an erroneous RA in Spitaler's original position. His source is Wolf's third list of nebulae from Heidelburg. Unfortunately, there is no object in Wolf's third list at the position of I834 (which is about 1.5 arcmin north of the IC position), so I do not know which object in WIII Dreyer was looking at. ===== IC 839 is a galaxy just where Bigourdan observed it, though it has been equated in the past with one or the other of the components of NGC 4851. Bigourdan's position for the IC object, reduced with respect to the GSC position for his reference star, falls within a few arcsec of the GSC position for the galaxy. ===== IC 841. In his sixth list, Wolf questions the identity of the galaxy he inserted under this number. He got the right object. ===== IC 845. Dreyer copies Swift's question mark on the declination into the IC. The declination is not too bad -- only 2 arcmin or so out. Swift's RA, however, is 22 seconds too far east. Aside from that, his description, including the "F * nr p" (the star is 3 arcmin west) is appropriate for the galaxy. The CGCG includes a faint companion about an arcmin to the east-southeast in the magnitude. A couple of faint stars must also be included. ===== IC 847 = NGC 4973. Swift's original position -- though not the IC position -- lands within an arcminute of NGC 4973, and his description ("vF, S, R, between 2 stars") fits, too. Interestingly, Howe (in MN 61, 29, 1900) states, "The description `between 2 stars' given in the Index Catalogue, I cannot verify from my sketch of the field of view." One possibility is that Howe's field was much smaller than Swift's unusually large one of 32 arcmin. The two stars are 9 arcmin apart, perhaps separated enough that Howe overlooked one of them. However, there is another more likely possibility: Howe was examining the wrong galaxy. His position for N4973 is almost identical to Swift's for I847, yet Howe listed it in his third list of "new" nebulae. Why did Howe mistake N4974 for I847? Dreyer made a mistake in precessing Swift's RA of I847 so that the IC RA is 30 seconds too large. This puts I847 so close to N4974 that Dreyer mistakenly equated the two when he got Reumker's correction to the positions of N4973 and N4974 (see N4967 for more discussion of the NGC objects). Howe obviously had not seen Reumker's corrections, though, or he would have realized that his "new" nebula was identical to N4973. This suggests that he thought that the nebula (which we now know as N4974) was I847. This would easily explain why he did not see Swift's stars: N4974 is not between two stars. Whatever the source of Howe's confusion, it's clear that Swift saw one of the galaxies that William Herschel had discovered a century earlier. Again, assuming Swift's position to be good in this case, that galaxy was probably N4973. ===== IC 853 = IC 4205, which see. ===== IC 864 and IC 866 are the northern-most two galaxies in a group of eight, seven with IC numbers from Swift and Javelle. Swift swept over the area in April of 1889, and Javelle followed in June of 1891. Javelle's positions are, of course, much better (but see IC 869 for a bit of a mystery), and there is little doubt as to which galaxies he saw. Swift's positions, though, are -- as is not uncommon -- not good enough to unambiguously identify the objects he found. Making the assumption that he saw the brightest five of the group, we can, however, make some pretty good guesses. (His descriptions are no help; four of the five are simply "eeF, pS, R". For IC 870, however, he adds a comment about "4 pB sts in a curve sf point to the 1st, 3rd, 4th, and 5th.") First, IC 868 and IC 870 are pretty clearly the close pair of galaxies on the southern edge of the group. These are the 1st and 3rd brightest in the group. Also, Swift comments that his "4th of 5" is a double with the 5th. Next, if Swift's relative positions are at all indicative, the 4th brightest, IC 867, is pretty clearly the 3rd of his five. This finally gets us to IC 864 and IC 866. Swift makes the relative positions just 2 arcmin apart in Dec; his RA is the same. However, on the sky, the 5th and 2nd brightest galaxies have nearly the same declination (only 4.3 arcsec different), but are separated in RA by just about 2 arcmin (1.94 arcmin to be exact). Perhaps Swift simply made a mistake in his observing notes or in his transcription of them. Whatever happened, these are the only two galaxies in the area that he might have seen, so we'll assume that he did indeed see them. That being the case, we must move Swift's name off the IC entry for IC 869 and put it on IC 864. ===== IC 866. There is no doubt about Javelle's identification of this object. However, see IC 864 for the uncertainty surrounding Swift's observations. IC 869 has more about Javelle's. ===== IC 867. As with the other group members, there is some uncertainty about Swift's observations of this. See IC 864 for more. Javelle's data are thankfully unambiguous on this object. See IC 869 for more about Javelle's micrometric observations in the group. ===== IC 868. This is one of two galaxies in the group clearly identified by Swift's note, "D with 5th [brightest]". See IC 864 for more about Swift's observations. IC 869 has more notes about Javelle's data for galaxies in the group. ===== IC 869 probably refers to both galaxies near Javelle's position. When that is corrected for a systematic offset seen in the other positions for the group galaxies (IC 864, 866-868, and 870), it falls very nearly midway between the two objects. Since they are about 30 arcsec apart, and both have small, bright nuclei, though, I would have expected Javelle to "resolve" them. Javelle's description "Faint, small, round, with little condensation" doesn't help us much at all. Still, it's clear that he saw something here, so I've used the IC number on both objects with positional suffixes. Since these are among the fainter galaxies in the group, Swift did not pick them up. See my comments on the other objects for more about Swift's observations. ===== IC 870 forms a close pair with IC 868 (which see). IC 864 and IC 869 have more information about the other group members. ===== IC 872, 877, 878, and 880. Swift recorded four new nebulae on 28 April 1891, one said in his description to be preceding, and the other three following, NGC 5060. Yet his positions put all of them at least a minute of time following the NGC galaxy. Except for the first, for which there are two candidates, none of the positions, as printed or "corrected" by a minute of time, has any galaxies or asterisms at all close. In particular, if his relative positions and descriptions of the following three objects were correct, there would be -- at least -- a striking triplet of galaxies in the area. But there isn't. Instead, there are three individual galaxies: NGC 5060, very close to its position measured by d'Arrest (who discovered it); UGC 8349, 11 seconds preceding the corrected position for I872; and UGC 8361, 6 seconds following and 1.5 arcmin south of Swift's printed position for I872. Given that Swift includes the note about N5060 in his description for I872, and that, for the only other nebula he found that night (IC 1016, which see), the RA is 1m 18s too large, I think that U8349 is I872. But U8361 is just as large and bright -- and therefore presumably as visible -- as U8349, so I've listed it as a possibility for I872, also. But for the other three, I see no reasonable candidates. I'm afraid that they, like many other of Swift's discoveries, are lost. ===== IC 877. See IC 872. ===== IC 878. See IC 872. ===== IC 879 = IC 4222, which see. ===== IC 880. See IC 872. ===== IC 884 and IC 887 were included in an appendix to the NGC, written after the main body of the catalogue had gone to press. Swift had somehow not included their positions and descriptions in the letters that he sent to Dreyer that Dreyer adopted for Swift's sixth list, finally published in its entirety while the NGC was in press. The positions for IC 887 in the appendix and in the sixth list agree. But those for IC 884 do not: the appendix -- and the first IC -- make the RA 1m larger than Swift's sixth list. Unfortunately, there are no galaxies at either position. Nor is there one at the position of IC 887 which is claimed to be "vF, vS; nearly bet 2 sts; [GC] 3517 [N5119] nr np." There are no galaxies near southeast of N5119 that Swift could have seen. Swift found three other galaxies the same night: NGC 3443, N3474, and N5122. With the exception of the declination for N3443 (8.3 arcmin too small), the positions for these three are not too bad. They average 7 seconds of time preceding and 0.3 arcmin south of the true positions, so give us no indication of a systematic offset. Even if we include the large declination error for N3443, we still have no real clues as to where Swift's other two objects might be. I personally think that he found two nebulae in the fairly rich area around NGC 5070 and NGC 5072, but I've been unable to find two reasonable candidates. So, two more of Swift's "novae" have to be declared lost, at least for now. ===== IC 887. See IC 884. ===== IC 888 = NGC 5136. Swift's position for IC 888, from his 8th list of "new" nebulae, is within 3 seconds of being exactly 1 minute of time off the NGC position (from the Herschels). Swift's description fits the object, so I suspect that he simply made a 1 minute error when reading the position from his setting circles. Another, though more remote, possibility for the identity of the IC object is CGCG 072-073. This has the correct right ascension, but the declination is 26 arcmin off and the object is considerably fainter than NGC 5136. Swift could have seen it -- but the 1 time-minute error for the brighter galaxy is more compelling. ===== IC 895 is lost -- unless it is an observation of NGC 5240. But neither Swift's description nor position fits the galaxy. In particular, the position is well off in both RA and Dec, and is not a digit error. Swift's comment "* in center ? D" (which Dreyer took to mean "sbM, D?"; could it be "* in center? D") does not fit N5240, either. The other three nebulae that Swift found the night of 1 September 1888 don't help at all with possible systematic offsets. Only one, IC 511, is near its nominal position, and Swift got the direction of a nearby "wide D *" wrong -- it is northwest, not southeast as Swift has it. The other two objects (IC 1028 and IC 1045, both of which see) are nowhere near their catalogued positions, and IC 1045 may well be lost, too. ===== IC 897. This number has almost always been applied to UGC 08544 = CGCG 102-016. However, Malcolm Thomson pointed out that Bigourdan's original description includes the note "Situated near NGC 5217 at PA = 105 deg, d = 3.5 arcmin." Since UGC 08544 is over 8 arcmin south of N5217, there is clearly something strange going on. That strange thing is simply that Bigourdan misidentified his comparison star. Instead of using BD +18 2750 as he did for N5217, he actually used BD +18 2754. When his measurements are reduced with respect to that star, they fall within about 12 arcsec of the closer companion of N5217. That brings up another question, however. Bigourdan's micrometric measurements are usually much closer to the mark than 12 arcsec. Curiously, his measurements of N5217 are also well off the galaxy, and in the same direction. In both cases, he has more than one measurement, and they are in accord with one another. I have not been able to work out his error, but there clearly is one somewhere in his observations of this pair on the night of 20 May 1890. In any event, the identification of IC 897 is now correct, thanks to Malcolm's diligence. ===== IC 907 is almost certainly UGC 8643. This identity was first suggested in CGCG, and is reasonable. The RA's are the same to well within Swift's usual error, and his Dec is just 20 arcmin off. This is probably a digit error. ===== IC 917 may be a star, but its companions (I918, 919, 921-3, 925, 926, 928-32, 934-38) are galaxies in Abell 1783. These were found by Burnham with the Lick 36-inch refractor in 1890. Barnard provides crude positions for them in AN 125, 380, 1890, copied correctly into the first IC. Barnard's positions and descriptions are not clear enough to positively identify more than four or five of the 18 galaxies in his table. One, I919, is called "cB" while the others are "vF" or "faint" and "vS, R." There are two pairs noted: I923 and I925, and I937 and I938. However, the positions imply the existence of two other pairs: I918 and I919, and I934 and I936. Faced with this puzzle, I wrote to Don Osterbrock at Lick to ask if Burnham's or Barnard's original observations are still extant. They are, but they turn out to be even more sketchy than the AN article, so are no help. Brent Archinal reports that Leos Ondra who, during an extended visit to several US observatories, has found that Barnard's original observing books at Yerkes are still kept in the library there. These may not help solve a mystery originating in the 36-inch dome at Lick, but they might be usefully examined, anyhow. All we can do now, however, is to assign the numbers, in approximate order of right ascension as given in AN, to the brightest 18 objects in the cluster, paying attention to the declinations when we can, as well as to the meager clues given in the descriptions. As I noted above, it seems likely that I917 is a star, but the remainder of the numbers can be assigned to galaxies without too much bending of Barnard's positions. However, I have to make it clear that there is a lot of guesswork going on here, and that these identifications really are tentative, pending uncovering more information. Hubble, by the way, in his PhD thesis at the University of Chicago (Publ. Yerkes Obs. IV, Part II, 1917) describes this area and lists positions of some of the galaxies in the field. He listed tentative identifications for only three of the galaxies: I921, I925, and I938. The identifications that I've adopted agree with Hubble's for I921 and I938, but not for I925 (Hubble has this as the galaxy at 13 41 22.7 +55 51 15 = I923, while I have the galaxy at 13 41 24.7 +55 52 00). ===== IC 918. See IC 917. ===== IC 919. See IC 917. ===== IC 921. See IC 917. ===== IC 922. See IC 917. ===== IC 923. See IC 917. ===== IC 925. See IC 917. ===== IC 926. See IC 917. ===== IC 928. See IC 917. ===== IC 929. See IC 917. ===== IC 930. See IC 917. ===== IC 931. See IC 917. ===== IC 932. See IC 917. ===== IC 934. See IC 917. ===== IC 935. See IC 917. ===== IC 936. See IC 917. ===== IC 937. See IC 917. ===== IC 938. See IC 917. ===== IC 945 is almost certainly UGC 08732 = CGCG 336-018. This is twice as large and twice as bright as CGCG 336-019, the galaxy identified in CGCG as IC 945. Swift's original position -- that copied correctly into the IC -- is much closer to the fainter galaxy, and his note of a "coarse D * nf points to it" could apply to either object. However, the idea that he should sweep up the fainter object while missing the brighter one just 3 arcmin away is difficult to accept (but see IC 997 and IC 998). ===== IC 953, IC 955, and IC 957 are lost, probably irretrievably. They are among Ormond Stone's novae in the extensive list of micrometric observations of nebulae published by the Leander McCormick observers in 1893. Apparently found during an observation of "GC 3697" (= NGC 5357), all four nebulae have several observations each, all referred to two stars. Thus, it is possible to lay out the relative positions of the nebulae and stars to form a clear picture of the field. This pattern is nowhere to be found near N5357. N5357 is probably an outlying member of the IC 4329 Group. I had the thought that the nebulae might be four in the core of the group. But the clear pattern of the four nebulae and two stars is not duplicated anywhere in the group. Nor can I find a similar pattern assuming that some of the novae are stars. So, "Not found" is the only reasonable conclusion. Here are some eye-glazing details. While it initially seems likely that Stone misidentified his comparison stars, a closer look at the problem shows that it is not as simple as that. He gives a precise position for one of the stars, and this one can be reliably identified with a GSC star at 13 50 58.01, -30 02 17.8 (B1950.0) -- Stone gives end figures of 58.04 and 17.1. However, reducing the measurements that he gives using this star gives positions in empty fields. Furthermore, his observations are not internally consistent: it should be possible to use the measurements from the "known" GSC star to pin down the other star by working through the positions for his nebulae. But this does not work: for the four objects involved, the derived positions for the unknown star (for which he gives only a crude position of 13 50 10, -30 04 again precessed to B1950) are several arcmin apart on the sky. Finally, again assuming that he used the identified GSC star to measure NGC 5357, his micrometric position for that galaxy ought to be close to the GSC position. Instead, the reduced position is 23.8 seconds east, and 1' 17" north of N5357. So, he obviously did not observe N5357. At this point, I quit wasting time and went on to the next puzzle. You may have more patience than I. Good luck! ===== IC 955. See IC 953. ===== IC 957. See IC 953. ===== IC 958 is almost certainly NGC 5360. Swift's description ("eeeF, pS, iR; seen only by glimpses") fits, and his typically crude position is only 3 arcmin away from Marth's galaxy. The only concern I have is that NGC 5364 is in the field -- why didn't Swift mention that, too? So, colons go on the IC number. ===== IC 973 = NGC 5467 and IC 974 are both stars near NGC 5468. They were found by Bigourdan while he was trying to recover the three "nebulae" seen by Tempel near NGC 5468. Bigourdan somehow became a bit confused by the field, so did not realize immediately that one of his "novae" (IC 973) was the same star that he took to be NGC 5467. He published it in his first Comptes Rendus list, so it got an IC number. He caught the identity later when he was preparing his complete observations for publication. See NGC 5465 for more. ===== IC 974 is probably the star 30 arcsec south of Bigourdan's estimated position. It is a bit fainter than NGC 5467 = IC 973, and would have been at the limit of Bigourdan's telescope. See IC 973 and NGC 5465 for more on this field. ===== IC 997 and IC 998 are perhaps the brightest and faintest galaxies in a group of four (the others are IC 4401 and MCG -01-37-002). Swift has these two objects entered in two of his lists ("(X)" and XI), but -- guessing here -- I think that he only observed them once, on 16 May 1892. His second "observation," claimed to be on 16 Sept 1896, reported in his long 11th list, looks to me like a hasty updating of the first, though perhaps after a quick second look at the field (it would have been low in the west just after sunset, though, not ideally placed for re-examination). The positions are just 10 seconds of time and 1.4 arcmin different, roughly the numbers one would expect from precession over the 10-year equinox difference (assuming that the short list in MNRAS 53, 273, 1893 has positions given for 1890.0). The descriptions are identical aside from the brightness of IC 997 ("vF" rather than "pF" in the earlier list). In particular, his note about the "star with distant companion near north" is worded the same in both lists. In other re-observations where Swift notes nearby stars, his wording is different (see e.g. NGC 5502 = NGC 5503). Howe has an extensive note about the group (in which he found a third object, IC 4401) in MNRAS 61, 46, 1900. Here he locates and measures the three galaxies that he and Swift saw, as well as the nearby star and its companion. He also notes the identity of Swift's nebulae in the two different lists. I have adopted his identities for the three galaxies -- though with questions. Keep reading. Malcolm has argued pretty persuasively that Swift probably saw the brightest two objects in the group, IC 997 and IC 4401. However, this would make Swift's positions not only further off in absolute terms, but his differences between his two objects would be off, too. Instead of the pretty good agreement with the actual differences of 20 seconds and 2.1 arcmin (Swift has 18 seconds and 1.0 arcmin), the differences would be 35 seconds and 4.2 arcmin. Also, the stars Swift mentions are much further from IC 4401 than they are from IC 997, though still within the 5 arcmin or so that he usually means when he uses the word "near" in his descriptions. Finally, IC 997 and IC 4401 are virtually equal in brightness (and surface brightness, too), while Swift's descriptions are quite different. He says "pF" or "vF" for I997 and "eeF" for I998. The galaxy that Howe and I take as I998 is a magnitude fainter than I997, more in keeping with Swift's descriptions. I also note that Howe saw only three of the four galaxies here, missing the MCG object, in spite of the fact that it is half a magnitude brighter than I998. So, we do indeed have a mystery: how could two seasoned observers miss seeing brighter objects in a group while picking up the faintest? Malcolm's argument is not without basis, so I've put colons and question marks on the identifications. ===== IC 998. See IC 997. =====