M 105 (NGC 3379) Galaxy group in Leo
includes NGC 3384 and NGC 3389
M 105 is located at: RA 10 hours 47 minutes 50 seconds, Dec +12 degrees 34 minutes 55 seconds
Size: 5.4' x 4.8' / 5.5' x 2.5' and 2.7' x 1.3'; Magnitude: 10.2 blue / 10.9 blue and 12.4 blue; Class: E1 / SB(s)0-: and SA(s)c
North is up

West to the right
| Telescope: |
8" f5 Newtonian reflector |
| Camera: |
ST-8XME self-guided, binned 1x1, temp -20c, camera control MaxIm DL 4.56 |
| Image: |
Lumicon Red filter, 500 minutes (500 x 10 minute subs) 05/1/2/3/ 2010; seeing 2.1-3.8 FWHM per CCDStack |
| Processing: |
CCDStack 1.7, Photoshop 7.0 |
| Location: |
Rolling Roof Observatory, Thousand Oaks, CA 91360 (+34d 13m 29s -118h 52m 20s) |
| Notes: |
The group is named after M 105 (centered, the large featureless E1 galaxy is the Westernmost object in the field), the elongated SB(s)o-: NGC 3384 next largest to the East (left), and finally the little spiral NGC 3389 SA(s)c. This is a reshoot of a 260 minute red-filtered image from 05/29/30/31/2006 ... didn't gain much from doubling the exposure. This image was taken with no moon, but hazy sky conditions (see M 65 and M 66). From the NGC / IC Project: Contemporary Visual Observation(s) for NGC 3379 NGC 3379 = M105 = U05902 = MCG +02-28-011 = CGCG 066-018 = PGC 32256 10 47 49.7 +12 34 57 V = 9.3; Size 5.4x4.8; SB = 12.8 13.1": bright, very small bright core, slightly elongated. First of three bright galaxies in the field with N3384 7.3' NW and N3389 9.7' ESE. 8": fairly bright, round. - by Steve GottliebContemporary Visual Observation(s) for NGC 3384 NGC 3371 = N3384: = U05911 = MCG +02-28-012 = CGCG 066-021 10 48 17.0 +12 37 49 See observing notes for N3384. N3771 was discovered by JH (h751) and described as "F, R. The second of 3 in a triangle." Peters claimed an observation but this object was not recovered by Rosse, Schultz, Bigourdan or Reinmuth. Just 1' W of Peter's position is a mag 15.1 star at 10 46 57.5 +13 47 31 (J2000) and 1' S is a mag 14 star at 10 47 01.3 +13 46 29 (possibly elongated on the DSS image?). Carlson identifed N3771 with a star based on Mount Wilson photographs. But, in NGCBUGS, Corwin argues that the trio Herschel is referring to is N3379, N3384 (h751 = N3371) and N3389 (h753 = N3373), as this trio matches the positions angles given in the observation of the first of the group. See NGCBUGS for discussion. - by Steve Gottlieb NGC 3384 = UGC 05911 = MCG +02-28-012 = CGCG 066-021 = N3371: = PGC 32292 10 48 17.0 +12 37 49 V = 9.9; Size 5.5x2.5; SB = 12.6; PA = 53d 13.1": bright, bright stellar nucleus, elongated 5:2 SW-NE. Second of three with M105 7.3' SW and N3389 6.4' SSE. 8": fairly bright, round, moderately large. - by Steve GottliebHistorical Research Notes / Correction for NGC 3384 NGC 3371 is probably NGC 3384, and NGC 3373 is probably NGC 3389. His descriptions are appropriate for the galaxies, and his measured position angles -- 68.4 deg between his first and second objects, and 156.8 deg between his second and third -- are a close match for those between N3379 and N3384 (66.5 deg), and N3384 and N3389 (154.7 deg), especially when precession is taken into account. However, JH has left us positions that suggest that these are companions of NGC 3367, not NGC 3379. His position for N3367, the nominal first of the three, exactly matches the position for that object measured on another night when the additional two objects were not seen. Added to this is his observation of N3389 on the same night the two questionable objects were seen. Even so, my feeling is that he has somehow confused his observations of N3367 and N3379 on the night when he also measured the two companions. Adding more mystery to the case is Peters's comment: "N3371] was distinctly seen by me 1880, Mar. 2; but 2198, the third of the `triple nebula,' could not be found." There are two faint stars within two arcmin of JH's nominal position for N3371; perhaps Peters saw one of these. Dreyer notes in the GC Supplement that no other observer had seen either N3371 or N3373 at JH's positions. - Dr. Harold G. Corwin, Jr. Contemporary Visual Observation(s) for NGC 3389 NGC 3373 = N3389: = U05914 = MCG +02-28-013 = CGCG 066-022 = PGC 32306 10 48 28.0 +12 31 59 See observing notes for N3389. Discovered by JH (h753) and described as "F, R, the last of 3 in a triangle." Not found by Bigourdan, Peters, Rosse, Schultz (who questioned whether this object and N3371 exists) or Reinmuth! Identified by Carlson as a star based on a Mount Wilson photograph. A mag 14.7 GSC star is near JH's position but Corwin feels there was a confusion on the first object in this "trio" which is actually N3379 and using the given position angles with respect to this galaxy, then N3373 = N3389 and N3371 = N3384. - by Steve Gottlieb NGC 3389 = UGC 05914 = MCG +02-28-013 = CGCG 066-022 = N3373: = PGC 32306 10 48 28.0 +12 31 59 V = 11.9; Size 2.8x1.3; SB = 13.2; PA = 112d 13.1": fairly faint, very elongated 3:1 WNW-ESE, diffuse. Third and faintest of three with bright galaxies N3384 6.4' NNW and M105 9.7' WNW. 8": faint, small. - by Steve GottliebHistorical Research Notes / Correction for NGC 3389 NGC 3371 is probably NGC 3384, and NGC 3373 is probably NGC 3389. His descriptions are appropriate for the galaxies, and his measured position angles -- 68.4 deg between his first and second objects, and 156.8 deg between his second and third -- are a close match for those between N3379 and N3384 (66.5 deg), and N3384 and N3389 (154.7 deg), especially when precession is taken into account. However, JH has left us positions that suggest that these are companions of NGC 3367, not NGC 3379. His position for N3367, the nominal first of the three, exactly matches the position for that object measured on another night when the additional two objects were not seen. Added to this is his observation of N3389 on the same night the two questionable objects were seen. Even so, my feeling is that he has somehow confused his observations of N3367 and N3379 on the night when he also measured the two companions. Adding more mystery to the case is Peters's comment: "N3371] was distinctly seen by me 1880, Mar. 2; but 2198, the third of the `triple nebula,' could not be found." There are two faint stars within two arcmin of JH's nominal position for N3371; perhaps Peters saw one of these. Dreyer notes in the GC Supplement that no other observer had seen either N3371 or N3373 at JH's positions. - Dr. Harold G. Corwin, Jr. |