NGC/IC Project Restoration Effort

===== NGC 5171 is the brightest galaxy in a curious group. "Curious" because, of the five NGC objects (N5171, N5176, N5177, N5178, and N5179) in it, only four were seen by any one observer. However, since at least two of the three observers were looking for Comet d'Arrest, they clearly picked up the nebulae as afterthoughts. First to go through the group was Hough, then directory of Dearborn Observatory in Chicago, and Burnham, apparently observing with Hough the night of 5 May 1883 on the 18.5-inch refractor. Though the positions are not particularly good, Burnham's offsets to the 8th magnitude star 21 seconds preceding and 58 arcsec south, pins down the nebula he saw as NGC 5171. Dreyer creditted Burnham with the co-discovery of NGC 5179, apparently because of the uncertain position. Hough is credited with NGC 5171, but he describes his object as "Double. Nebula, round, condensed." This could apply to NGC 5171 and its superposed compact companion or star, but it could also apply to NGC 5176 and NGC 5177 which are 2-3 arcmin north-northeast of NGC 5171. Hough's position is not good enough to tell. It also seems odd that he would record the same nebula as new as Burnham, especially given that they were observing on the same night with the same telescope. On 11 May of the same year, Tempel saw NGC 5171, N5178, and N5179 with the 10.5-inch Amici I refractor at Arcetri. He has micrometric positions for the first two, but the third was apparently too far from his comparison star to be measured. Nevertheless, his estimated position for it is good enough to positively identify the galaxy. Finally, on 29 June 1883, Ernst Hartwig, using the 18-inch refractor at Strassburg found and measured four nebulae in the group: N5171, N5176, N5177, and N5179. His positions are very good. So, the observers using the larger telescopes failed to find the faintest of the nebulae, N5178. But it is the southern-most of the five, and has a lower average surface brightness, so may not draw attention to itself as readily as the northern four.

===== NGC 5171 17.5" (5/27/95): faint, small, round, very small brighter core, faint 40" halo. A faint star is superimposed NW of the core. Forms the NE vertex of a right triangle with two mag 9 stars are 5.3' WSW and 6.8' SW. Brightest of five in a tight group (MKW 11) with NGC 5176 2.9' N, NGC 5177 3.8' N, NGC 5179 2.4' ENE and NGC 5178 7' SSE.