New General Catalog Objects: NGC 4900 (original) (raw)

QuickLinks:
4900, 4901, 4902, 4903, 4904, 4905, 4906, 4907, 4908, 4909, 4910, 4911, 4912, 4913, 4914, 4915, 4916,
4917, 4918, 4919, 4920, 4921, 4922, 4923, 4924, 4925, 4926, 4927, 4928, 4929, 4930, 4931, 4932, 4933,
4934, 4935, 4936, 4937, 4938, 4939, 4940, 4941, 4942, 4943, 4944, 4945, 4946, 4947, 4948, 4949

Page last updated Sep 5, 2023 (Added Caldwell & other IDs for NGC 4945)
Page last updated Sep 6, 2021
Minor modifications of de Vaucouleurs entries, Arp 176
Checked Corwin's 'final' positions
NEXT: Check Steinicke designations, magnitudes, types (later, compare to Corwin, NED, LEDA, Gottlieb)
Prior last update June 3, 2021
Updated formatting: update captions / alt tags, image order as needed
Checked Steinicke primary databases
Entered all Dreyer NGC entries, including notes/IC1/IC2/1912 entries), all historical references
Checked Corwin positions
WORKING 4900: Include notes by Gottlieb, some for inclusion, some for my own reference.
NEXT: Check cross-indices using LEDA/NED/SIMBAD
NEXT: See checklist for previous 3 pages

NGC 4900 (= PGC 44797 = UGC 8116 = CGCG 043-093 = MCG +01-33-035)
Discovered (Apr 30, 1786) by William Herschel
Also observed (Apr 7, 1828) by John Herschel
A magnitude 11.4 spiral galaxy (type SB(rs)c) in Virgo (RA 13 00 39.1, Dec +02 30 05)

Historical Identification: Per Dreyer, NGC 4900 (= GC 3356 = JH 1509 = WH I 143, 1860 RA 12 53 34, NPD 86 45.0) is "considerably bright, considerably extended, 10th magnitude star attached at 135°±."
Discovery Note: In the notes for the NGC Dreyer quotes JH re "h 1509" being the same as WH I 143. Due to an erratum in the Philosophical Transactions list of WH's discoveries, the position of I 143 was 1° 13' too far to the south, which error was copied by Arthur von Auwers in his compilation converting WH's awkward positions (so far east or west and north or south relative to some star) to right ascension and declination (a tremendous aid for those trying to figure out where WH's objects were located).
Physical Information: 2.2 by 2.1 arcmin.
Use By The de Vaucouleurs Atlas: NGC 4900 is used by the de Vaucouleurs Atlas of Galaxies as an example of galaxy type (R')SB(s)cd.

SDSS image of region near spiral galaxy NGC 4900
Above, a 12 arcmin wide SDSS image centered on NGC 4900
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4900

NGC 4901 (= PGC 44684 = UGC 8112 = CGCG 245-009 = MCG +08-24-019)
Discovered (Mar 7, 1831) by John Herschel
A magnitude 14.5 elliptical galaxy (type E1) in Canes Venatici (RA 12 59 56.4, Dec +47 12 20)

Historical Identification: Per Dreyer, NGC 4901 (= GC 3357 = JH 1512, 1860 RA 12 53 35, NPD 42 01.8) is "pretty faint, small, round, gradually brighter middle."
Physical Information: 1.3 by 1.2 arcmin

SDSS image of region near elliptical galaxy NGC 4901
Above, a 12 arcmin wide SDSS image centered on NGC 4901
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of elliptical galaxy NGC 4901

NGC 4902 (= PGC 44847 = UGCA 315 = MCG -02-33-092)
Discovered (Feb 8, 1785) by William Herschel
Also observed (May 8, 1831) by John Herschel
A magnitude 10.9 spiral galaxy (type SB(rs)b) in Virgo (RA 13 00 59.7, Dec -14 30 49)

Historical Identification: Per Dreyer, NGC 4902 (= GC 3358 = JH 1511 = WH I 69, 1860 RA 12 53 38, NPD 103 45.9) is "pretty bright, pretty large, irregularly round, star near."
Discovery Note: In the notes for the NGC Dreyer justifies equating JH 1511 and WH I 69 by quoting a note by JH in the GC. In that, JH quotes his aunt, Caroline Herschel, who informed him that I 69 was one of three nebulae that were 7 arcmin further north than in the printed catalog, and that a disagreement in the positions pointed out in Arthur von Auwers' catalog of the Herschel objects was due to an error in her calculations. (She did all the calculations [called "reductions"] for her brother's observations, and the work she did was difficult and painstaking, and despite considerable skill and effort, a number of errors were made or discovered over the years, such as when she redid all the original calculations to bring their positions up to the Equinox of 1800; and when JH was preparing his GC, she sent him extensive notes on errors in his father's catalog that she felt he needed to be made aware of.)
Physical Information: 3.2 by 2.9 arcmin (from the images below).
Use By The de Vaucouleurs Atlas: NGC 4902 is used by the de Vaucouleurs Atlas of Galaxies as an example of galaxy type SB(

r

s)b.

>PanSTARRS image of region near spiral galaxy NGC 4902, also showing possible(?) companion PGC 924035
Above, a 12 arcmin wide PanSTARRS image centered on NGC 4902, also showing PGC 924035
Below, a 3.5 by 3.2 arcmin wide image of the galaxy
(Image Credit & © Carnegie-Irvine Galaxy Survey; used by permission)
Carnegie-Irvine image of spiral galaxy NGC 4902

PGC 924035
Not an NGC object but listed here as a possible companion of NGC 4902
A magnitude 16.5(?) spiral galaxy (type Scd?) in Virgo (RA 13 00 44.7, Dec -14 29 06)

Physical Information: It appears that there is absolutely nothing available for this galaxy other than rough estimates of its brightness and size (about 0.5 by 0.07 arcmin (from the images below), so whether it is a companion of NGC 4902 or (probably more likely) a much more distant background galaxy is unknown.

PanSTARRS image of spiral galaxy PGC 924035
Above, a 0.9 arcmin wide PanSTARRS image of PGC 924035; for a wide-field image see NGC 4902
The "bright" star to the northwest is magnitude 12.8

NGC 4903 (= PGC 44894 = ESO 443-030 = MCG -05-31-013)
Discovered (Mar 30, 1835) by John Herschel
A magnitude 12.9 spiral galaxy (type SB(rs)c) in Centaurus (RA 13 01 22.8, Dec -30 56 06)

Historical Identification: Per Dreyer, NGC 4903 (= GC 3359 = JH 3450, 1860 RA 12 53 44, NPD 120 12.0) is "very faint, considerably small, round, star attached, preceding (western) of 2," the other being NGC 4905.
Physical Information: 1.6 by 1.3 arcmin. A Seyfert galaxy (type Sy 2).

DSS image of region near spiral galaxy NGC 4903, also showing lenticular galaxy NGC 4905
Above, a 12 arcmin wide DSS image centered on NGC 4903, also showing NGC 4905 and PGC 44918
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4903

NGC 4904 (= PGC 44846 = UGC 8121 = CGCG 015-055 = MCG +00-33-026)
Discovered (Jan 1, 1786) by William Herschel
A magnitude 12.0 spiral galaxy (type SB(s)cd) in Virgo (RA 13 00 58.6, Dec -00 01 38)

Historical Identification: Per Dreyer, NGC 4904 (= GC 3361 = WH II 517, 1860 RA 12 53 48, NPD 89 16.0) is "pretty bright, pretty small, round, brighter middle."
Physical Information: 2.2 by 1.5 arcmin. A starburst galaxy.

SDSS image of region near spiral galaxy NGC 4904
Above, a 12 arcmin wide SDSS image centered on NGC 4904
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4904

NGC 4905 (= PGC 44902 = ESO 443-031 = MCG -05-31-015)
Discovered (Mar 30, 1835) by John Herschel
A magnitude 13.3 lenticular galaxy (type SB0+(s) pec) in Centaurus (RA 13 01 30.7, Dec -30 52 06)

Historical Identification: Per Dreyer, NGC 4905 (= GC 3360 = JH 3451, 1860 RA 12 53 51, NPD 120 10.0) is "very faint, very small, round, suddenly a little brighter middle, following (eastern) of 2," the other being NGC 4903.
Physical Information: 1.8 by 1.1 arcmin. (For now, see the wide-field image of NGC 4903.)

PGC 44918 (= ESO 443-034 = MCG -05-31-018)
Not an NGC object but listed here as a possible companion of NGC 4905
A magnitude 13(?) galaxy (type (R')SAB(rs)0/a? pec) in [Centaurus](<a) (RA 13 01 41.7, Dec -30 54 44)

Physical Information:
NED RIDE1 84 Mpc, 1.5 x 1.1 arcmin, 3K Vr 5637 km/sec

NGC 4906 (= PGC 44799 = CGCG 160-253)
Discovered (Apr 6, 1864) by Heinrich d'Arrest
A magnitude 14.1 elliptical galaxy (type E1) in Coma Berenices (RA 13 00 39.8, Dec +27 55 26)

Historical Identification: Per Dreyer, NGC 4906 (= GC 5702, d'Arrest, 1860 RA 12 53 53, NPD 61 19.5) is "very faint, very small, 15th magnitude star preceding (to the west)."
Physical Information: 0.48 by 0.43 arcmin.

NGC 4907 (= PGC 44819 = PGC 1827957 = CGCG 160-257 = MCG +05-31-089)
Discovered (May 5, 1864) by Heinrich d'Arrest
A magnitude 13.6 spiral galaxy (type SB(rs)b) in Coma Berenices (RA 13 00 48.8, Dec +28 09 30)

Historical Identification: Per Dreyer, NGC 4907 (= GC 5703, d'Arrest, 1860 RA 12 54 02, NPD 61 05.3) is "extremely faint, very small, 13th magnitude star attached." The position precesses to RA 13 00 47.1, Dec +28 09 23, just off the southwestern rim of the galaxy listed above, the description fits and there is nothing comparable nearby, so the identification is certain.
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 6145 km/sec (and H0 = 70 km/sec/Mpc), NGC 4907 is about 285 million light-years away, substantially further than a single redshift-independent distance estimate of about 195 million light-years (though in good agreement with the HST press release that places the galaxy in the Coma Cluster, about 270 million light-years away). Given that and its apparent size of about 1.0 by 1.0 arcmin (from the images below), the galaxy is about 80 to 85 thousand light-years across.

SDSS image of region near spiral galaxy NGC 4907, also showing IC 4040 and IC 4045
Above, a 12 arcmin wide SDSS image centered on NGC 4907, also showing IC 4040 and 4045
Below, a 1.5 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4907
Below, a 1.25 by 1.5 arcmin wide image of the galaxy (Image Credit ESA/Hubble & NASA, M. Gregg)
HST image of spiral galaxy NGC 4907
Below, a 0.45 arcmin wide image of the central region (Image Credit as above)
HST image of spiral galaxy NGC 4907

NGC 4908 (probably = PGC 44832 = UGC 8129 = CGCG 160-259 = MCG +05-31-090)
Discovered (Apr 11, 1785) by William Herschel
Discovered (Apr 22, 1865) by Heinrich d'Arrest
A magnitude 13.2 elliptical galaxy (type E2) in Coma Berenices (RA 13 00 54.5, Dec +28 00 28)

Historical Identification: Per Dreyer, NGC 4908 (= GC 5704, d'Arrest, 1860 RA 12 54 05, NPD 61 13.1) is "very faint, very small." The position precesses to RA 13 00 50.2, Dec +28 01 35, which falls between two galaxies in the Coma Cluster of galaxies, the fainter northwestern of which has generally been listed as NGC 4908, and the brighter southeastern as IC 4051. However, per a suggestion by Malcolm, Corwin feels that this assignment is probably backwards, as discussed below; and there is also the question of why, if William Herschel observed the region (as listed above), Dreyer makes no mention of it in the NGC. As to the question of historical priority, Herschel recorded his observation of the area as (WH) III 363, that is, number 363 in a list of faint nebulae (he lists it as a "very faint" nebula at a position 6m 16s west and 23 arcmin north of 41 Comae Berenices). Unfortunately, John Herschel's catalog incorrectly assigned that observation to GC 3354 (= NGC 4894), which of course has a different position from NGC 4908, and although the NGC entry for NGC 4894 questions its identity with WH III 363, it does not reassign Herschel's observation to what became NGC 4908, nor could it correct the GC error during the period prior to the publication of the NGC; so d'Arrest was bound to think that he had discovered a previously unknown nebula, and it was quite reasonable for Dreyer to give him credit for that discovery. As to the question of which galaxy is which entry, we should first calculate Herschel's position. The 'current' (J2000.0) position of 41 Com precesses to RA 12 56 51.3, Dec +28 46 42 (relative to the Equinox corresponding to Herschel's observation of 1785), so Herschel's observation must have been at about 1785 RA 12 50 35.3, Dec +29 09 42. That precesses to 'current' RA 13 00 58.2, Dec +27 59 58, just southeast of the brighter southeastern galaxy mentioned above, so it appears reasonably certain that Herschel's observation was of that object (PGC 44832, as shown in the title for this entry). Malcolm and Corwin both feel that d'Arrest probably also observed the nearly half magnitude brighter southeastern galaxy, and if so, then the galaxy usually listed as IC 4051 should be called NGC 4908 (as in this entry), and vice-versa (as discussed at the entry for IC 4051). However, regardless of which galaxy corresponds to which listing, the fact that some references list the galaxies with one set of designations, and other references list them exactly the opposite way means that any reference to NGC 4908 or IC 4051 tells the reader almost nothing about which galaxy is under consideration; so it would be best to refer to them by more modern designations, such as the PGC listings used on this site, or by their positions.
Physical Information: (Apparent size of PGC 44832 is 1.0 by 0.8 arcmin.)

SDSS image of region near elliptical galaxy PGC 44832, which is probably NGC 4908, but is often called IC 4051. Also shown is PGC 44828, which is probably IC 4051, but is often called NGC 4908. Also shown are NGC 4906, IC 4040, 4041, 4042 and 4045
Above, a 12 arcmin wide SDSS image centered on PGC 44832, which is probably NGC 4908;
also shown are PGC 44828, NGC 4906, IC 4040, 4041, 4042 and 4045
Below, a 2.4 arcmin wide SDSS image of PGC 44832, which is probably NGC 4908
SDSS image of elliptical galaxy PGC 44832, which is probably NGC 4908, but is often called IC 4051

NGC 4909 (= PGC 44949 = ESO 269-035 = MCG -07-27-028)
Discovered (Jun 5, 1834) by John Herschel
A magnitude 12.7 spiral galaxy (type (R')SA(rs)a) in Centaurus (RA 13 02 01.9, Dec -42 46 17)

Historical Identification: Per Dreyer, NGC 4909 (= GC 3362 = JH 3452, 1860 RA 12 54 09, NPD 132 00.9) is "extremely faint, 3 or 4 stars of 11th and 12th magnitude following (to the east)."
Physical Information: 1.9 by 1.7 arcmin.
Use By The de Vaucouleurs Atlas: NGC 4909 is used by the de Vaucouleurs Atlas of Galaxies as an example of galaxy type (R')SA(l)a.

DSS image of region near spiral galaxy NGC 4909
Above, a 12 arcmin wide DSS image centered on NGC 4909
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4909

SERIOUS PROBLEMS HERE

NGC 4910 (perhaps = NGC 4845 and if so, = PGC 44392 = UGC 8078 = CGCG 015-049 = MCG +00-33-025)
Discovered (Jan 24, 1784) by William Herschel (and later listed as NGC 4910)
Discovered (Feb 24, 1786) by William Herschel (and later listed as NGC 4845)
Probably a lost object in Virgo RA 13 01 18.6, Dec +01 39 12, or
If = NGC 4845, a magnitude 11.2 spiral galaxy (type SA(s)ab) in Virgo (RA 12 58 01.2, Dec +01 34 33)

Historical Identification: Per Dreyer, NGC 4910 (= GC 3363 = WH V 3, 1860 RA 12 54 10, NPD 87 35.5) is "extremely faint, very large, partially resolved, some stars seen." The position precesses to RA 13 01 18.6, Dec +01 39 12, but there is nothing there. Per Corwin, Dreyer quotes Herschel as stating "The place of this nebula is not determined with accuracy", and adds "No modern observations known", which would seem to make any identification difficult or impossible. However, Corwin adds that Herschel determined the position of V 3 relative to the same star as a nebula for which Dreyer states "RA 40 seconds too great", suggesting that Herschel might have placed the position well to the east of the actual nebula. If so, then the relatively bright galaxy listed as NGC 4845 is a tempting (and for that matter, the only) candidate for what Herschel observed; but even taking into account the error in the comparison star the position is relatively far from that galaxy, and Herschel's description of his V 3 does not match his description of what became NGC 4910 (??? something wrong here ???), so equating NGC 4910 with NGC 4845 is considered the only possibility, but is by no means certain, and "lost" is probably a better conclusion.
Discovery Note: In the notes for the NGC, Dreyer states that the position of V 3 in Arthur von Auwers' catalog of Herschel's nebulae was 10 minutes of time too great due to an error in Auwers' calculations. Unfortunately, as discussed above, none of the errors that were later recognized helped to nail down the position of the nebula.

NGC 4911 (= PGC 44840 = UGC 8128 = CGCG 160-260 = MCG +05-31-093)
Discovered (Apr 11, 1785) by William Herschel
Also observed (Apr 6, 1864) by Heinrich d'Arrest
nox 165 A magnitude 12.8 spiral galaxy (type SAB(r)bc) in Coma Berenices (RA 13 00 56.1, Dec +27 47 27)

Historical Identification: Per Dreyer, NGC 4911 (= GC 3364 = WH II 392, d'Arrest, 1860 RA 12 54 10, NPD 61 27.3) is "the 1st of 4, faint, pretty large, 11th magnitude star 2 arcmin north-preceding (to the northwest)," the "other" 3 of 4 being NGC 4919, 4921 and 4923.
Physical Information: Apparent size 1.2 by 1.1 arcmin. Probably a companion of PGC 83751.

SDSS image of region near spiral galaxy NGC 4911; also shown are NGC 4919 and PGC 83751, which is also called NGC 4911A
Above, a 12 arcmin wide region centered on NGC 4911, also showing NGC 4919 and PGC 83751
Below, a 2.4 arcmin wide SDSS image of NGC 4911 and PGC 83751
SDSS image of spiral galaxy NGC 4911 and PGC 83751, which is also known as NGC 4911A

PGC 83751 (= "NGC 4911A")
Not an NGC object but listed here because sometimes called NGC 4911A
A magnitude 14.9 lenticular galaxy (type S0) in Coma Berenices (RA 13 00 54.1, Dec +27 47 01)

Physical Information: Apparent size 0.4 by 0.2 arcmin. A probable companion of NGC 4911, which see for images.

MUCH MORE TO FOLLOW HERE; part of "a fine mess"

NGC 4912 (not = NGC 4922) (but perhaps/probably = PGC 44908 = UGC 8137 = CGCG 160-099 = MCG +05-31-100)
Recorded (Apr 24, 1865) by Lawrence Parsons, 4th Lord Rosse
A lost or nonexistent object in Canes Venatici (RA 13 00 46.3, Dec +37 22 41), or
A magnitude 13.6 lenticular galaxy (type S0??) in Coma Berenices (RA 13 01 33.6, Dec +29 07 50)

Historical Identification: Per Dreyer, NGC 4912 (= GC 5705, 4th Lord Rosse, 1860 RA 12 54 12, NPD 51 52 ), is one of "two nebulae (the other being NGC 4913), north of and in line with h1514 (?)," JH 1514 being NGC 4914. Note that the question mark does not mean that the identity of JH 1514 is in doubt; that is certainly NGC 4914. What it means is that for the reasons discussed below, Dreyer wasn't sure that the galaxy involved was h 1514 (and in fact, there is absolutely no chance that it was). The position precesses to RA 13 00 46.3, Dec +37 22 41, which is north of NGC 4914, but there is nothing there save for NGC 4914. The simplest conclusion is that neither NGC 4912 nor 4913 represent real objects, but per Corwin, Lord Rosse did make a sketch of the area, but it looks nothing like the field near NGC 4914, so it is more likely that he misidentified the "reference" galaxy, and observed a completely different region (hence Dreyer's decision to put a question mark next to the reference to h1514). In that case the observations may represent real objects, but as described below considerable efforts to identify the field of view have been unconvincing, and I suspect that what Lord Rosse saw will never be determined.
Note About the 4th Earl: The observations of what became NGC 4912, 4913 and 4916 were done during the lifetime of the 3rd Earl, so although the 4th Earl almost certainly did them, he wasn't actually the 4th Earl or Lord Rosse at the time, but Lord Oxmantown; he only became Lord Rosse when his father died, two years later.
A "Summary" Of Lord Rosse's Observations: The key to what Lord Rosse observed on Apr 24, 1865 is presumably in his paper (read in 1878, published in 1880) describing all observations made at Birr Castle by him and his father, from 1848 to 1878. Under the entry for JH 1514, which became NGC 4914, there are three entries. The second, made on Apr 5, 1877, only describes JH 1514, and though suggests the possibility of two additional nebulae, states that the speculum was in bad condition, and whether those nebulae, seen "by glimpses", is uncertain. The third, describing observations on Apr 1, 1878, describes JH 1514 and three additional nebulae; the positions and descriptions for those nebulae make it absolutely certain that they were NGC 4893 and 1870 (attributed in the NGC to Lord Rosse, but Steinicke credits Dreyer with 4893) and 4868 (which is not credited to either Dreyer or Lord Rosse in the NGC, since it was discovered by William Herschel nearly a century earlier). So far, so good. However, as shown by the entries on this page for NGC 4812, 4813 and 4816, the three nebulae 'discovered' by Lord Rosse on Apr 24, 1865 all appear to be lost or nonexistent, and the sketch of them and what is presumably JH 1514 bears absolutely no resemblance to the field near that galaxy (NGC 4914). Per Corwin, multiple searches were made over a period of years, trying to find a field of view that contained something resembling Lord Rosse's sketch (shown below). After Corwin, Ron Buta and Sue French purchased originals of Lord Rosse's lists of nebulae from the 7th Earl, Sue suggested that the quartet of galaxies in the field shown below might be what Lord Rosse had seen, in which case either NGC 4922 or IC 4088 would be the galaxy that Rosse (and/or Dreyer) mistook for JH 1514 (but much more about will follow once the rest of this page is a bit further along).
As can be seen in the comparison of the image of the region with Lord Rosse's skethc, the relative position of the galaxies in the sky more or less matches the ones in Lord Rosse's sketch, down to the double star between the northeastern galaxy and the others. However, the star supposedly to the west of the northernmost galaxy does not appear to exist (it would out of the field of view in the image, but it isn't anywhere in a much wider view, either); and the brightest galaxy is the northernmost one, whereas Lord Rosse stated that it was Beta in his sketch, which is the southernmost one. So though the pattern of galaxies is in some ways tempting, the correspondence between the quartet and what Rosse sketched and wrote is not as good as might be required to be convincing, especially since the quartet is 8 degrees to the south of JH 1514, which requires considerable confusion on Lord Rosse's part about where his telescope was pointing to even imagine. There are also some other discrepancies in the description, but they could be ignored, if it weren't for the problems already noted. For that reason, though Corwin states that he likes Sue French's suggestion, whence my mentioning it, he isn't convinced that it is correct, and places question marks on the identifications.

<valign=center>DSS image of region near NGC 4922, IC 843, IC 4088 and PGC 49733, which may or may not be the region observed by the 4th Lord Rosse on Apr 24, 1865Drawing by the 4th Lord Rosse of what he observed on Apr 24, 1865

Above left, a 12 by 24 arcmin wide DSS image showing the region near NGC 4922, IC 843, IC 4088 and PGC 49733, with west on the right and north on top. Above right, Lord Rosse's drawing of what he thought was the region near NGC 4914, with west on the right (and probably north on top, as it provides the best match to the image on the left).

NGC 4913
(Another fine mess Parsons created)
Recorded (Apr 24, 1865) by Lawrence Parsons, 4th Lord Rosse
A lost or nonexistent object in Canes Venatici (RA 13 00 46.4, Dec +37 20 41)
Perhaps(??) IC 843 (perhaps IC 4088) at (RA 13 01 43.4, Dec +29 02 41) (seems very unlikely, but see NGC 4916)

Historical Identification: Per Dreyer, NGC 4913 (= GC 5706, 4th Lord Rosse, 1860 RA 12 54 12, NPD 51 54 ), is one of "two nebulae (the other being NGC 4912), north of and in line with h1514(?)," JH 1514 being NGC 4914. Note that the question mark does not mean that the identity of JH 1514 is in doubt; that is certainly NGC 4914. What it means is that for the reasons discussed in the entry for NGC 4912, Dreyer wasn't sure that the galaxy involved was h 1514 (and in fact, there is absolutely no chance that it was). The second IC notes "Not seen with certainty on Heidelberg plate (Wolf list V). (only seen once at Birr)." The position precesses to RA 13 00 46.4, Dec +37 20 41, which is just north of NGC 4914, but there is nothing there except for NGC 4914. The simplest conclusion is that neither NGC 4912 nor 4913 represent real objects, but per Corwin, Lord Rosse did make a sketch of the area, and it looks nothing like the field near NGC 4914, so it is more likely that he misidentified the "reference" galaxy, and observed a completely different region (hence Dreyer's decision to put a question mark next to the reference to h1514). In that case the observations may represent real objects, but considerable efforts to identify the field of view have been fruitless (though as shown by the reference to IC 843 and IC 4088 continually being made), and it appears most likely that what Lord Rosse saw will never be determined.
Note About An Apparent Companion: Corwin lists a possible companion, basedd on the presumption that NGC 4913 is IC 843; but since whether that is true is as up in the air as the galaxy itself, the supposed companion will not be discussed here, but only following the entry for IC 843, itself.

NGC 4914 (= PGC 44807 = UGC 8125 = CGCG 189-013 = MCG +06-29-014)
Discovered (Mar 17, 1787) by William Herschel
Also observed (Apr 28, 1827) by John Herschel
A magnitude 11.6 elliptical galaxy (type E4) in Canes Venatici (RA 13 00 42.9, Dec +37 18 55)

Historical Identification: Per Dreyer, NGC 4914 (= GC 3365 = JH 1514 = WH II 645, 1860 RA 12 54 12, NPD 51 55.8) is "pretty bright, considerably small, round, suddenly much brighter middle, 17th magnitude star north-preceding (to the northwest)." The position precesses to RA 13 00 46.4, Dec +37 18 53, right on the galaxy, so the identification is certain.
Physical Information: Apparent size 3.5 by 2.1 arcmin.

NGC 4915 (= PGC 44891 = UGCA 318 = MCG -01-33-069)
Discovered (Mar 11, 1787) by William Herschel
Also observed (Mar 12, 1826) by John Herschel
A magnitude 12.1 elliptical galaxy (type E2) in Virgo (RA 13 01 28.2, Dec -04 32 47)

Historical Identification: Per Dreyer, NGC 4915 (= GC 3366 = JH 1513 = WH IV 47, 1860 RA 12 54 15, NPD 93 46.8) is "pretty bright, small, round, brighter middle."
Physical Information: Apparent size 1.6 by 1.3 arcmin.

NGC 4916
(Yet another blunder by Parsons)
Recorded (Apr 24, 1865) by Lawrence Parsons, 4th Lord Rosse
A lost or nonexistent object in Canes Venatici (RA 13 00 54.5, Dec +37 21 40)
Corwin suggests that this might be PGC 44973 at RA 13 02 04.2, Dec +29 15 12 ("possible", but see NGC 4912)

Historical Identification: Per Dreyer, NGC 4916 (= GC 5707, 4th Lord Rosse, 1860 RA 12 54 20, NPD 51 53 ), is "a nebula, north-following (northeast of) h1514(?)," JH 1514 being NGC 4914. Note that the question mark does not mean that the identity of JH 1514 is in doubt; that is certainly NGC 4914. What it means is that for the reasons discussed in the entry for NGC 4912, Dreyer wasn't sure that the galaxy involved was h 1514 (and in fact, there is absolutely no chance that it was). The position precesses to RA 13 00 54.2, Dec +37 21 42, a few arcmin northeast of NGC 4914, but there is nothing there save for NGC 4914 (the situation is similar to NGC 4912 and 4913, which were recorded by Lord Rosse on the same night). The simplest conclusion is that NGC 4916 does not represent a real object, but per Corwin, Lord Rosse did make a sketch of the area, and it looks nothing like the field near NGC 4914, so it is more likely that he misidentified the "reference" galaxy, and observed a completely different region (hence Dreyer's decision to put a question mark next to the reference to h1514). In that case the observation may represent a real object, but considerable efforts to identify the field of view have been fruitless, and it appears most likely that what Lord Rosse saw will never be determined.

NGC 4917 (= PGC 44838 = UGC 8130 = CGCG 245-011= MCG +08-24-023)
Discovered (Mar 20, 1828) by John Herschel
A magnitude 13.8 spiral galaxy (type (R')SB(s)b) in Canes Venatici (RA 13 00 55.6, Dec +47 13 20)

Historical Identification: Per Dreyer, NGC 4917 (= GC 3367 = JH 1515, 1860 RA 12 54 27, NPD 42 01.9) is "extremely faint, small, extended, brighter middle."
Physical Information: Apparent size 1.5 by 1.0 arcmin.

SDSS image of region near spiral galaxy NGC 4917
Above, a 12 arcmin wide SDSS image centered on NGC 4917
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4917

NGC 4918 (= PGC 44934)
Discovered (1886) by Francis Leavenworth
A magnitude 14.4 spiral galaxy (type SA(rs)b?) in Virgo (RA 13 01 50.6, Dec -04 30 02)

Historical Identification: Per Dreyer, NGC 4918 (Leavenworth list II (#457), 1860 RA 12 54 33, NPD 93 45.3) is "extremely faint, extremely small, round, brighter middle and nucleus, h1513 4' south-preceding (to southwest)," (JH) 1513 being NGC 4915. The position precesses to RA 13 01 46.7, Dec -04 30 34, just over an arcmin west-southwest of the galaxy listed above, NGC 4915 is indeed to its southwest (though more like 6 arcmin distant), the description is otherwise reasonable and there is nothing else nearby, so the identification is certain.
Physical Information: Based on a recessional velocity relative to the Cosmic Background Radiation of 10165 km/sec (and H0 = 70 km/sec/Mpc), a straightforward calculation indicates that NGC 4918 is about 470 to 475 million light-years away. However, for objects at such distances we should take into account the expansion of the Universe during the time it took their light to reach us. Doing that shows that the galaxy was about 455 million light-years away at the time the light by which we see it was emitted, about 460 to 465 million years ago (the difference between the two numbers being due to the expansion of the intervening space during the light-travel time). Given that and its apparent size of about 0.72 by 0.27 arcmin (from the images below), the galaxy is about 95 thousand light-years across.

PanSTARRS image of region near spiral galaxy NGC 4918, also showing NGC 4915
Above, a 12 arcmin wide PanSTARRS image centered on NGC 4918, also showing NGC 4915
Below, a 1 arcmin wide PanSTARRS image of the galaxy
PanSTARRS image of spiral galaxy NGC 4918

NGC 4919 (= PGC 44885 = UGC 8133 = CGCG 160-094 = MCG +05-31-097)
Discovered (May 5, 1864) by Heinrich d'Arrest
A magnitude 14.1 lenticular galaxy (type (R')SA0 ?(r)) in Coma Berenices (RA 13 01 17.6, Dec +27 48 33)

Historical Identification: Per Dreyer, NGC 4919 (= GC 5708, d'Arrest, 1860 RA 12 54 35, NPD 61 26.0) is "very faint, very small, 2nd of 4," the "other" 3 of 4 being NGC 4911, 4921 and 4923.
Physical Information: 1.1 by 0.7 arcmin

NGC 4920 (= IC 4134 = PGC 44958 = MCG -02-33-094)
Discovered (1882) by Wilhelm Tempel (and later listed as NGC 4920)
Discovered (Apr 16, 1895) by Guillaume Bigourdan (and later listed as IC 4134)
A magnitude 13.5 irregular galaxy (type IB(s)m) in Virgo (RA 13 02 04.3, Dec -11 22 44)

Historical Identification: Per Dreyer, NGC 4920 (Tempel list V, 1860 RA 12 54 35, NPD 100 44) is "very faint."
Physical Information: Apparent size 1.0 by 0.7 arcmin. Also known as IC 4134 (which see for a discussion of the duplicate listing).

DSS image of region near irregular galaxy NGC 4920
Above, a 12 arcmin wide DSS image centered on NGC 4920
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of irregular galaxy NGC 4920

NGC 4921 (= PGC 44899 = UGC 8134 = CGCG 160-095 = MCG +05-31-098)
Discovered (Apr 11, 1785) by William Herschel
Also observed (Apr 2, 1827) by John Herschel
A magnitude 12.2 spiral galaxy (type SB(rs)ab) in Coma Berenices (RA 13 01 26.1, Dec +27 53 10)

Historical Identification: Per Dreyer, NGC 4921 (= GC 3368 = JH 1516 = WH II 393, 1860 RA 12 54 39, NPD 61 21.8) is "faint, pretty large, 3rd of 4," the "other" 3 of 4 being NGC 4911, 4919 and 4923.

Physical Information: 2.4 by 2.1 arcmin

SDSS image of region near spiral galaxy NGC 4921, also showing NGC 4919 and 4923
Above, a 12 arcmin wide SDSS image centered on NGC 4921, also showing NGC 4919 and 4923
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4921
Below, a ? arcmin wide image of the galaxy
(Image Credit NASA/ESA/K. Cook (Lawrence Livermore National Laboratory))
HST image of spiral galaxy NGC 4921

NGC 4922 (almost certainly not = NGC 4912) (= UGC 8135 = CGCG 160-096 = MCG +05-31-099) (= PGC 44896 + PGC 86794)
Discovered (Apr 19, 1865) by Heinrich d'Arrest
A pair of galaxies in Coma Berenices (RA 13 01 24.9, Dec +29 18 40)
PGC 44896 = A magnitude 13.0 spiral galaxy (type Sb? pec) at RA 13 01 24.5, Dec +29 18 30
PGC 86794 = A magnitude 14.2 spiral galaxy (type SABa? pec) at RA 13 01 25.3, Dec +29 18 50

Historical Identification: Per Dreyer, NGC 4922 (= GC 5709, d'Arrest, 1860 RA 12 54 42, NPD 59 56.0) is "pretty bright, small, round, a little brighter middle, 11th or 12th magnitude star following (to the east)."
Physical Information: NED01 Apparent size 1.3 by 1.2 arcmin. A Seyfert galaxy (type?). Apparently interacting with NED02, which is about 0.6 by 0.5 arcmin(?). A Seyfert galaxy (type Sy 2).

SDSS image of region near spiral galaxies PGC 44896 and PGC 86794, which comprise NGC 4922
Above, a 12 arcmin wide SDSS image centered on NGC 4922
Below, a 2.4 arcmin wide SDSS image of PGC 44896 and PGC 86794, which comprise NGC 4922
SDSS image of spiral galaxies PGC 44896 and PGC 86794, which comprise NGC 4922

NGC 4923 (= PGC 44903 = CGCG 160-097 = MCG +05-31-101)
Discovered (Apr 11, 1785) by William Herschel
Also observed (Apr 2, 1827) by John Herschel
A magnitude 13.7 lenticular galaxy (type E/SB0) in Coma Berenices (RA 13 01 31.8, Dec +27 50 51)

Historical Identification: Per Dreyer, NGC 4923 (= GC 3369 = JH 1518 = WH II 394, 1860 RA 12 54 45, NPD 61 23.8) is "very faint, 4th of 4," the "other" 3 of 4 being NGC 4911, 4919 and 4921.
Physical Information: 0.8 by 0.8 arcmin

NGC 4924 (= PGC 44977 = MCG -02-33-096)
Discovered (May 8, 1831) by John Herschel
A magnitude 12.8 spiral galaxy (type (R')SAB(rs)bc? pec) in Virgo (RA 13 02 12.8, Dec -14 58 11)

Historical Identification: Per Dreyer, NGC 4924 (= GC 3370 = JH 1517, 1860 RA 12 54 51, NPD 104 13.2) is "considerably faint, large, very little extended 45°±." The position precesses to RA 13 02 13.6, Dec -14 58 27, only 0.3 arcmin southeast of the center of the galaxy listed above and well within its outline, the description fits and there is nothing else nearby, so the identification is certain. However, there is an unrelated galaxy (PGC 44952) less than 6 arcmin to the northwest which could be misidentified as a companion of the NGC object, so the "optical double" is discussed in the following entry.
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 5185 km/sec (and H0 = 70 km/sec/Mpc), NGC 4924 is about 240 to 245 million light-years away. Given that and its apparent size of about 1.95 by 1.45 arcmin (from the images below), the galaxy is about 135 to 140 thousand light-years across.
Classification Note: Prior to March 29, 2021 (when this entry was created) all references listed this as a lenticular galaxy (though NED's classification as (R')SAB(s)0/a pec? wasn't much different from the spiral classification in the description line for this entry), but even DSS2 images, though not showing the central region very well, make it obvious that it is probably a spiral; and the PanSTARRS images shown here, by revealing the central region in detail, make it clear that the galaxy is a spiral, and not a lenticular.

PanSTARRS image of region near spiral galaxy NGC 4924, also showing PGC 44952
Above, a 12 arcmin wide PanSTARRS image centered on NGC 4924, also showing PGC 44952
Below, a 2.25 arcmin wide PanSTARRS image of NGC 4924
PanSTARRS image of spiral galaxy NGC 4924
Below, a 1 arcmin wide PanSTARRS image of the central part of the galaxy
PanSTARRS image of the central part of spiral galaxy NGC 4924

PGC 44952 (= MCG -02-33-093)
Not an NGC object but listed here because not a companion of NGC 4924
A magnitude 13.5(?) spiral galaxy (type S(s)c?) in Virgo (RA 13 02 03.3, Dec -14 52 58)

Purpose Of This Entry: In the wide-field image of NGC 4924, PGC 44952 looks like it might be a companion of the NGC object, and since such a companion could help explain the peculiar structure of the NGC object, some people might wonder whether it really is such a companion (for instance, Gottlieb notes that NGC 4924 "forms a pair with MCG -02-33-093," which might easily be misinterpreted as "forms a physical pair"). This entry serves to lay any such idea to rest, as it shows that PGC 44952 is 170 million light-years closer to us than NGC 4924, so the two galaxies are only an optical double.
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 1675 km/sec (and H0 = 70 km/sec/Mpc), PGC 44952 is about 75 to 80 million light-years away, in good agreement with redshift-independent distance estimates of about 75 to 110 million light-years. Given that and its apparent size of about 1.1 by 0.6 arcmin (from the images below), the galaxy is about 25 thousand light-years across.

PanSTARRS image of region near spiral galaxy PGC 44952, also showing NGC 4924
Above, a 12 arcmin wide PanSTARRS image centered on PGC 44952, also showing NGC 4924
Below, a 1.5 arcmin wide PanSTARRS image of PGC 44952
PanSTARRS image of spiral galaxy PGC 44952

NGC 4925 (= PGC 44967 = MCG -01-33-074)
Discovered (Mar 23, 1789) by William Herschel
Also observed (Mar 16, 1828) by John Herschel
A magnitude 13.1 lenticular galaxy (type S0) in Virgo (RA 13 02 07.4, Dec -07 42 39)

Historical Identification: Per Dreyer, NGC 4925 (= GC 3371 = JH 1519 = WH II 779, 1860 RA 12 54 51, NPD 96 57.7) is "considerably faint, small."
Physical Information: 1.0 by 0.7 arcmin

NGC 4926 (= PGC 44938 = UGC 8142 = CGCG 160-103 = MCG +05-31-103)
Discovered (Apr 6, 1864) by Heinrich d'Arrest
A magnitude 13.0 lenticular galaxy (type E/S0) in Coma Berenices (RA 13 01 53.7, Dec +27 37 28)

Historical Identification: Per Dreyer, NGC 4926 (= GC 5710, d'Arrest, 1860 RA 12 55 07, NPD 61 37.3) is "pretty bright, small, round, gradually a little brighter middle."
Physical Information: Apparent size 1.1 by 1.0 arcmin. (For now, see the wide-field image of PGC 44968.)

PGC 44968 (= "NGC 4926A") (= CGCG 160-106 = MCG +05-31-107)
Not an NGC object but listed here because sometimes called NGC 4926A
A magnitude 14.2 lenticular galaxy (type SB0 pec?) in Coma Berenices (RA 13 02 07.9, Dec +27 38 54)

Physical Information: Apparent size 0.7 by 0.4 arcmin.

SDSS image of region near lenticular galaxy PGC 44968, also known as NGC 4926A; also shown are NGC 4926, and PGC 83758, also known as NGC 4926B
Above, a 12 arcmin wide SDSS image centered on PGC 44968, also showing NGC 4926 and PGC 83758
Below, a 2.4 arcmin wide SDSS image of PGC 44968
SDSS image of lenticular galaxy PGC 44968, also known as NGC 4926A

PGC 83758 (= "NGC 4926B")
Not an NGC object but listed here because sometimes called NGC 4926B
A magnitude 15.3 lenticular galaxy (type SB0) in Coma Berenices (RA 13 02 01.0, Dec +27 39 11)

Physical Information: Apparent size 0.6 by 0.3 arcmin.

SDSS image of lenticular galaxy PGC 83758, also known as NGC 4926B
Above, a 2.4 arcmin wide SDSS image of PGC 83758; for a wide-field view, see PGC 44968

NGC 4927 (= PGC 44945 = CGCG 160-105 = MCG +05-31-104)
Discovered (Apr 11, 1785) by William Herschel
Also observed (May 5, 1864) by Heinrich d'Arrest
A magnitude 13.8 lenticular galaxy (type E/S0) in Coma Berenices (RA 13 01 57.6, Dec +28 00 21)

Historical Identification: Per Dreyer, NGC 4927 (= GC 3372 = WH III 364, d'Arrest, 1860 RA 12 55 13, NPD 61 14.8) is "very faint."
Physical Information: Apparent size 0.6 by 0.4 arcmin.

NGC 4928 (= PGC 45052 = MCG -01-33-075)
Discovered (Apr 25, 1784) by William Herschel
Also observed (May 5, 1836) by John Herschel
A magnitude 12.5 spiral galaxy (type SA(s)bc pec) in Virgo (RA 13 03 00.5, Dec -08 05 06)

Historical Identification: Per Dreyer, NGC 4928 (= GC 3373 = GC 3374 = JH 3453 = WH II 190 = WH III 760, 1860 RA 12 55 43, NPD 97 19.5) is "faint, pretty small, very little extended, gradually a little brighter middle."
Discovery Note: In the notes for the NGC, Dreyer writes that GC 3374 = WH III 760 was identical to GC 3373 = WH II 190, "as already suspected by Marth and Auwers. No nebula (was) seen by d'Arrest in the place where GC 3374 (III 760) should be."
Physical Information: Apparent size 1.1 by 0.9 arcmin.

DSS image of region near spiral galaxy NGC 4928
Above, a 12 arcmin wide DSS image centered on NGC 4928
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4928

NGC 4929 (= PGC 45027 = CGCG 160-113 = MCG +05-31-111)
Discovered (Apr 20, 1865) by Heinrich d'Arrest
A magnitude 13.4 elliptical galaxy (type E1) in Coma Berenices (RA 13 02 44.4, Dec +28 02 43)

Historical Identification: Per Dreyer, NGC 4929 (= GC 5711, d'Arrest, 1860 RA 12 55 59, NPD 61 12.3) is "faint, small, 16th magnitude star close preceding (to the west)."
Physical Information: Apparent size 0.8 by 0.75 arcmin.

SDSS image of region near elliptical galaxy NGC 4929, also showing NGC 4931, IC 4111 and IC 4106
Below, a 12 arcmin wide SDSS image centered on NGC 4929, also showing NGC 4931, IC 4106 and IC 4111
Below, a 2.4 arcmin wide SDSS image of NGC 4929
SDSS image of elliptical galaxy NGC 4929

NGC 4930 (= PGC 45155 = ESO 323-074 = MCG -07-27-029)
Discovered (Jun 8, 1834) by John Herschel
A magnitude 11.1 spiral galaxy (type SB(rs)b) in Centaurus (RA 13 04 05.2, Dec -41 24 41)

Historical Identification: Per Dreyer, NGC 4930 (= GC 3375 = JH 3454, 1860 RA 12 56 15, NPD 130 39.8) is "very faint, round, in a triangle with stars of 8th and 9th magnitude following (to the east)."
Physical Information: Apparent size 4.4 by 3.6 arcmin.
Use By The de Vaucouleurs Atlas: NGC 4930 is used by the de Vaucouleurs Atlas of Galaxies as an example of galaxy type SB(rs)

b

c.

DSS image of region near spiral galaxy NGC 4930
Above, a 12 arcmin wide DSS image centered on NGC 4930
Above, a 5 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4930

NGC 4931 (= PGC 45055 = UGC 8154 = CGCG 160-118 = MCG +05-31-114)
Discovered (May 10, 1863) by Heinrich d'Arrest
A magnitude 13.5 lenticular galaxy (type S0) in Coma Berenices (RA 13 03 00.9, Dec +28 01 57)

Historical Identification: Per Dreyer, NGC 4931 (= GC 5712, d'Arrest, 1860 RA 12 56 17, NPD 61 13.3) is "faint, small."
Physical Information: Apparent size 1.6 by 0.6 arcmin.

NGC 4932 (= PGC 45015 = UGC 8150 = CGCG 270-040 = MCG +09-21-089)
Discovered (Apr 26, 1789) by William Herschel
A magnitude 13.6 spiral galaxy (type SA(r)c) in Canes Venatici (RA 13 02 37.7, Dec +50 26 18)

Historical Identification: Per Dreyer, NGC 4932 (= GC 3376 = WH III 818, 1860 RA 12 56 20, NPD 38 47.5) is "considerably faint, small, round, very gradually a little brighter middle."
Physical Information: Apparent size 1.5 by 1.3 arcmin.

SDSS image of region near spiral galaxy NGC 4932
Above, a 12 arcmin wide SDSS image centered on NGC 4932
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4932

PGC 214058
Not an NGC object but listed here as a possible companion of NGC 4932
A magnitude 16(?) spiral galaxy (type SBc?) in Canes Venatici (RA 13 02 23.1, Dec +50 26 02)

Physical Information: LEDA V 16(?), SBc, 3K Vr 7314 km/sec; NED 14.7 mag, 3K Vr 7314 km/sec, z 0.024397

"PGC 4011826" (= SDSS J130240.77+502624.4)
Not an NGC object but listed here as a possible companion of NGC 4932
A magnitude 17.5(?) spiral galaxy (type S?) in Canes Venatici (RA 13 02 40.8, Dec +50 26 24)

Note About PGC Designation: Although HyperLEDA assigned a PGC designation to this galaxy, a search of the database for that designation returns no result, so it is shown in quotes. The SDSS designation or the position must be used for any database search.
Physical Information: LEDA 3K Vr 7220 km/sec; NED 7209 km/sec (z = 0.024048), but also lists z = 0.2186665, which must be for some nearby (or near-"digit") object and mis-assigned to this object.

NGC 4933 (= IC 4176 = "NGC 4933A/B", and with IC 4173 = Arp 176) (= PGC 45146 = MCG -02-33-102)
Discovered (May 9, 1784) by William Herschel (and later listed as NGC 4933)
Discovered (Apr 16, 1895) by Guillaume Bigourdan (and later listed as IC 4176)
A magnitude 11.7 lenticular galaxy (type S0/a pec) in Virgo (RA 13 03 57.0, Dec -11 29 48)

Historical Identification: Per Dreyer, NGC 4933 (= GC 3377 = WH II 191, 1860 RA 12 56 28, NPD 100 45.0) is "pretty bright, pretty large, irregularly round." (See IC 4176 for a discussion of the double listing.)
Warning About Non-Standard Designations: As shown above, this galaxy is listed as NGC 4933, IC 4176 and NGC 4933A. The last designation is pointless, since the galaxy has a perfectly good IC designation, and confusing, as there is no standard for adding letters to NGC/IC designations, and a given galaxy may have two or more "letter" designations, and if so, those same letters may be used for a completely different galaxy, raising the very real risk that data belonging to one object may be assigned to another one (in fact, NGC 4933A and NGC 4933B are interchangeably used for both IC 4173 and IC 4176, depending on the reference). For all these reasons, non-standard "letter" designations should never be used, and are only shown here as a warning against their use.
Physical Information: Apparent size 2.0 by 1.1 arcmin. Vr 2965 km/sec. Interacting with and tidally distorted by IC 4173, with which it forms Arp 176, and probably part of a group with PGC 45143, which appears to be at about the same distance.
Use By The Arp Atlas: NGC 4933 is used (with IC 4173) by The Arp Atlas of Peculiar Galaxies as an example of a galaxy with a diffuse counter-tail, with the note "Companion galaxy very condensed," that companion being IC 4173.

DSS image of lenticular galaxy NGC 4933 (sometimes called NGC 4933A or even NGC 4933B) and elliptical galaxy IC 4173 (sometimes called NGC 4933B or even NGC 4933A), collectively known as Arp 176; also shown are PGC 45143, which is sometimes called NGC 4933C, and PGC 45169, which is sometimes misidentified as IC 4134
Above, a 12 arcmin wide DSS image centered on NGC 4933 and IC 4173
Also shown are PGC 45143 and PGC 45169
Below, a 3.0 arcmin wide DSS image of NGC 4933, IC 4173 and PGC 45143
DSS image of lenticular galaxy NGC 4933 and elliptical galaxy IC 4173 (sometimes called NGC 4933B or even NGC 4933A), collectively known as Arp 176; also shown is PGC 45143, which is sometimes called NGC 4933C
Below, a ? arcmin wide image of the three galaxies (Image Credit Arp Atlas of Peculiar Galaxies)
Arp Atlas image of lenticular galaxy NGC 4933 and elliptical galaxy IC 4173 (sometimes called NGC 4933B or even NGC 4933A), collectively known as Arp 176; also shown is PGC 45143, which is sometimes called NGC 4933C
Below, a ? arcmin wide image of the group (Image Credit & © Carnegie-Irvine Galaxy Survey; used by permission)
(The original label has been removed because it uses inappropriate non-standard designations)
Carnegie-Irvine Galaxy Survey image of NGC 4933, IC 4173 and PGC 45143

IC 4173 (with NGC 4933 = Arp 176) (= PGC 45142 = MCG -02-33-101 = "NGC 4933B/A")
Discussed at its IC entry, but also listed here because sometimes called NGC 4933B or NGC 4933A
A magnitude 14.2 elliptical galaxy (type E2 pec) in Virgo (RA 13 03 54.6, Dec -11 30 20)

Warning About Non-Standard Designations: As noted in the entry for NGC 4933, that galaxy is sometimes pointlessly called NGC 4933A (and sometimes, even NGC 4933B), and as shown above, IC 4173 is sometimes pointlessly called NGC 4933B (and sometimes, NGC 4933A). In that warning I pointed out that sometimes a given "letter" designation is applied to more than one galaxy, causing confusion, and the risk that data belonging to one galaxy is incorrectly assigned to another one. That is certainly the case here, as depending on the reference, both IC 4173 and 4176 are interchangeably referred as both NGC 4933A and 4933B, and as a result, it is very likely that these mis-designations can or have led to mistakes in their data and descriptions. For that reason, such non-standard letter designations should never be used, and are shown here only as a warning.
Historical and Physical Information: For anything else, see the regular entry for IC 4173.

PGC 45143 (= MGC -02-33-103 = "NGC 4933C")
Not an NGC object but listed here because sometimes called NGC 4933C
A magnitude 15.3 irregular galaxy (type Im pec) in Virgo (RA 13 04 01.2, Dec -11 29 26)

Warning About Non-Standard Designations: As discussed in the entries for NGC 4933 and IC 4173, for a variety of reasons, non-standard "letter" designations should never be used, and are shown here only as a warning.
Physical Information: Apparent size 0.5 by 0.4 arcmin. Vr 3190 km/sec. Probably part of a group with NGC 4933 (which see for images) and IC 4173, which comprise Arp 176.

NGC 4934 (= PGC 45082 = UGC 8160 = CGCG 160-120 = MCG +05-31-115)
Discovered (Apr 20, 1865) by Heinrich d'Arrest
A magnitude 14.4 lenticular galaxy (type S0/a) in Coma Berenices (RA 13 03 16.2, Dec +28 01 49)

Historical Identification: Per Dreyer, NGC 4934 (= GC 5713, d'Arrest, 1860 RA 12 56 28, NPD 61 12.9) is "faint, small, a little extended."
Physical Information: Apparent size 1.0 by 0.2 arcmin.

NGC 4935 (= PGC 45093 = UGC 8159 = CGCG 100-023 = MCG +03-33-023)
Discovered (Apr 17, 1887) by Lewis Swift
A magnitude 13.0 spiral galaxy (type (R')SAB(s)b) in Coma Berenices (RA 13 03 21.2, Dec +14 22 39)

Historical Identification: Per Dreyer, NGC 4935 (Swift list VI (#50), 1860 RA 12 56 36, NPD 74 51.7) is "very faint, very small, round, 3 stars following (to the east)."
Physical Information: Apparent size 1.2 by 1.0 arcmin.

SDSS image of region near spiral galaxy NGC 4935
Above, a 12 arcmin wide SDSS image centered on NGC 4935
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4935

NGC 4936 (= PGC 45174 = ESO 443-047 = MCG -05-31-028)
Discovered (May 6, 1834) by John Herschel
A magnitude 10.7 elliptical galaxy (type E1) in Centaurus (RA 13 04 17.1, Dec -30 31 34)

Historical Identification: Per Dreyer, NGC 4936 (= GC 3378 = JH 3456, 1860 RA 12 56 39, NPD 119 46.4) is "pretty bright, small, round, brighter middle, star following (to the east) 6 seconds of time."
Physical Information: Apparent size 2.7 by 2.3 arcmin.

NGC 4937 (= ESO 269-?40)
Discovered (Mar 3, 1837) by John Herschel
A star group in Centaurus (RA 13 04 51.5, Dec -47 13 08)
Corwin also lists an alternate position at RA 13 04 45.2, Dec -47 13 08 (which is much closer to Herschel's position)

Historical Identification: Per Dreyer, NGC 4937 (= GC 3379 = JH 3455, 1860 RA 12 56 43, NPD 136 28.0) is "most extremely faint, small, round, preceding (western) of 2", the other being NGC 4940 (which see for an image of the group). The position precesses to RA 13 04 45.5, Dec -47 13 09, a few seconds west of a compact group of just over half a dozen very faint stars. Per Corwin, the position relative to NGC 4940, although not exact, is adequate to establish the identity of the group.
Physical Information: Apparent size 0.5 arcmin.

NGC 4938 (= PGC 45044 = CGCG 270-042 = MCG +09-21-091)
Discovered (Feb 17, 1831) by John Herschel
A magnitude 14.3 spiral galaxy (type SABa?) in Canes Venatici (RA 13 02 57.6, Dec +51 19 07)

Historical Identification: Per Dreyer, NGC 4938 (= GC 3380 = JH 1521, 1860 RA 12 56 48, NPD 37 55.3) is "extremely faint, round, pretty suddenly brighter middle."
Physical Information: Apparent size 0.8 by 0.7 arcmin.

SDSS image of region near spiral galaxy NGC 4938
Above, a 12 arcmin wide SDSS image centered on NGC 4938
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4938

PGC 2391991
Not an NGC object but listed here as a possible companion of NGC 4938
A magnitude ? galaxy (type ?) in Canes Venatici (RA 13 03 00.1, Dec +51 18 46)
Corwin lists a companion (PGC 2391991) at

PGC 3441785
Not an NGC object but listed here as a possible companion of NGC 4938
A magnitude ? galaxy (type ?) in Canes Venatici (RA 13 03 00.9, Dec +51 18 24)
(Wikisky mistakenly lists both PGC 2391991 and PGC 3441785 as PGC 2391991)

NGC 4939 (= PGC 45170 = MCG -02-33-104)
Discovered (Mar 25, 1786) by William Herschel
Also observed (May 6, 1836) by John Herschel
A magnitude 11.3 spiral galaxy (type SA(s)bc) in Virgo (RA 13 04 14.3, Dec -10 20 22)

Historical Identification: Per Dreyer, NGC 4939 (= GC 3381 = JH 3458 = WH II 561, 1860 RA 12 56 57, NPD 99 35.7) is "pretty bright, large, round, gradually much brighter middle."
Physical Information: Apparent size 5.5 by 2.8 arcmin. A Seyfert galaxy (type Sy 2).
Use By The de Vaucouleurs Atlas: NGC 4939 is used by the de Vaucouleurs Atlas of Galaxies as an example of galaxy type SAB(r)bc.

NOAO image of region near spiral galaxy NGC 4939 overlaid on a DSS background to fill in missing areas
Above, a 12 arcmin wide NOAO/DSS image centered on NGC 4939
(Image Credit Adam Block/NOAO/AURA/NSF)
Below, a 6 arcmin wide image of the galaxy (Image Credit as above)
NOAO image of spiral galaxy NGC 4939

NGC 4940 (= PGC 45235 = ESO 269-042)
Discovered (Mar 3, 1837) by John Herschel
A magnitude 12.3 spiral galaxy (type Sa) in Centaurus (RA 13 05 00.2, Dec -47 14 13)

Historical Identification: Per Dreyer, NGC 4940 (= GC 3382 = JH 3457, 1860 RA 12 56 58, NPD 136 29.4) is "faint, small, round, following (eastern) of 2," the other being NGC 4937.
Physical Information: Apparent size 1.0 by 1.0 arcmin.

DSS image of region near spiral galaxy NGC 4940; also shown, just to the northwest of the galaxy, is the compact group of faint stars listed as NGC 4937
Above, a 12 arcmin wide DSS image centered on NGC 4940, also showing NGC 4937
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4940

*Carnegie-Irvine Image of 4941 now available*

NGC 4941 (= PGC 45165 = UGCA 321 = MCG -01-33-077)
Discovered (Apr 24, 1784) by William Herschel
Also observed (Apr 16, 1828) by John Herschel
A magnitude 11.1 spiral galaxy (type (R)SAB(rs)ab?) in Virgo (RA 13 04 13.1, Dec -05 33 06)

Historical Identification: Per Dreyer, NGC 4941 (= GC 3383 = JH 1520 = WH I 40, 1860 RA 12 56 59, NPD 94 48.4) is "pretty faint, large, extended, gradually brighter middle and very bright nucleus, mottled but not resolved."
Physical Information: Apparent size 4.2 by 2.7 arcmin. A Seyfert galaxy (type Sy 2).

NOAO image of region near spiral galaxy NGC 4941 superimposed on a DSS background to fill in missing areas
Above, a 12 arcmin wide NOAO/DSS composite image centered on NGC 4941
(Image Credit George Seitz/Adam Block/NOAO/AURA/NSF)
Below, a 4.5 arcmin wide NOAO image of the galaxy (Image Credit as above)
NOAO image of spiral galaxy NGC 4941
Below, a ? arcmin wide image of its central regions (Image Credit Hubble Legacy Archive, Wikimedia Commons)
Partially processed HST image of central portion of spiral galaxy NGC 4941

NGC 4942 (probably = IC 4136) (= PGC 45177 = MCG -01-33-078)
Discovered (Mar 23, 1789) by William Herschel (and later listed as NGC 4942)
Discovered (July, 1899) by DeLisle Stewart (and later listed as IC 4136)
A magnitude 13.0 spiral galaxy (type SAB(s)d?) in Virgo (RA 13 04 19.1, Dec -07 38 58)

Historical Identification: Per Dreyer, NGC 4942 (= GC 3384 = WH III 761, 1860 RA 12 57 00, NPD 96 55.5) is "very faint, small." (see IC 4136 for a discussion of the probable duplicate listing)
Physical Information: Apparent size 1.6 by 1.3 arcmin. (Note: The VST image shown below is a preliminary image from a new survey of the Southern skies intended to eventually provide coverage for those regions similar to that of the Northern sky by the SDSS; it is presented as an example of the improvement in image quality that should soon be readily available for regions currently covered only by much older images obtained with now "ancient" technology.)

DSS image of region near spiral galaxy NGC 4942
Above, a 12 arcmin wide DSS image centered on NGC 4942
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4942
Below, a ? arcmin wide preliminary image from a new survey (Image Credit VST)
Preliminary VST survey sample: image of spiral galaxy NGC 4942

NGC 4943 (= PGC 45129 = CGCG 160-122)
Discovered (Apr 20, 1865) by Heinrich d'Arrest
A magnitude 14.4 lenticular galaxy (type SAB0) in Coma Berenices (RA 13 03 44.9, Dec +28 05 03)

Historical Identification: Per Dreyer, NGC 4943 (= GC 5714, d'Arrest, 1860 RA 12 57 02, NPD 61 09.7) is "very faint, very small."
Physical Information: Apparent size 0.5 by 0.3 arcmin.

NGC 4944 (= PGC 45133 = UGC 8167 = CGCG 160-124 = MCG +05-31-118)
Discovered (Apr 11, 1785) by William Herschel
Also observed (Apr 19, 1827) by John Herschel
A magnitude 12.9 lenticular galaxy (type S0/a?) in Coma Berenices (RA 13 03 49.9, Dec +28 11 09)

Historical Identification: Per Dreyer, NGC 4944 (= GC 3385 = JH 1522 = WH II 395, 1860 RA 12 57 05, NPD 61 03.6) is "faint, small, round, brighter middle, 9th magnitude star north-following (to the northeast) 1 arcmin."
Physical Information: Apparent size 1.5 by 0.5 arcmin. NED 3K Vr 7231 km/sec, z 0.02412029

PGC 214061
Not an NGC object but listed here as a probable companion of NGC 4944
A magnitude 15.5(?) lenticular galaxy (type SAB0?) in Coma Berenices (RA 13 03 54.9, Dec +28 11 15)

Physical Information:
LEDA SB?, B 16.2, I 14.9 -> V 15.5?; NED S0, 3K Vr 7135 km/sec, z 0.02379995

PGC 1828510
Not an NGC object but listed here as an apparent/possible companion of NGC 4944
A magnitude 17.3(?) elliptical galaxy (type E4?) in Coma Berenices (RA 13 03 50.4, Dec +28 10 43)

Physical Information:
LEDA E 4-5, B 17.7, I 16.5 -> V 17 to 17.5; NED 3K Vr 6648 km/sec

NGC 4945 ( C83 = PGC 45279 = PGC 3096217 = ESO 219-024)
Discovered (Apr 29, 1826) by James Dunlop
Also observed (Mar 31, 1835) by John Herschel
A magnitude 8.4 spiral galaxy (type SB(s)cd?) in Centaurus (RA 13 05 27.2, Dec -49 28 05)

Historical Identification: Per Dreyer, NGC 4945 (= GC 3386 = JH 3459, Dunlop #411, 1860 RA 12 57 14, NPD 138 32.1) is "bright, very large, very much extended 38.7°."
Physical Information: Apparent size 19.8 by 4.0 arcmin.

ESO image of region near spiral galaxy NGC 4945 overlaid on a DSS background to fill in missing areas; also shown is PGC 45380, also known as NGC 4945A
Above, a 30 arcmin wide ESO/DSS image centered on NGC 4945, also showing PGC 45380
(Image Credit above and below ESO)
Below, an 18 arcmin wide image of NGC 4945
ESO image of spiral galaxy NGC 4945

PGC 45380 (= ESO 219-028 = "NGC 4945A")
Not an NGC object but listed here because sometimes called NGC 4945A
A 12th magnitude spiral galaxy (type SB(s)m?) in Centaurus (RA 13 06 33.3, Dec -49 41 33)

Physical Information: Apparent size 2.5 by 1.6 arcmin.

DSS image of region near spiral galaxy PGC 45380, also known as NGC 4945A
Above, a 12 arcmin wide DSS image centered on PGC 45380 (also see wide-field image of NGC 4945)
Below, a 2.4 arcmin wide DSS image of the galaxy (nearly lost in glare from 8th magnitude HD 113767)
DSS image of spiral galaxy PGC 45380, also known as NGC 4945A

NGC 4946 (= PGC 45283 = ESO 269-045 = MCG -07-27-030)
Discovered (Jun 3, 1834) by John Herschel
A magnitude 12.4 elliptical galaxy (type E3) in Centaurus (RA 13 05 29.4, Dec -43 35 28)

Historical Identification: Per Dreyer, NGC 4946 (= GC 3387 = JH 3460, 1860 RA 12 57 32, NPD 132 50.9) is "bright, pretty small, round, gradually pretty much brighter middle, preceding (western) of 2," the other being NGC 4950.
Physical Information: Apparent size 1.6 by 1.2 arcmin.

NGC 4947 (= IC 3974) (= PGC 45269 = ESO 382-005 = MCG -06-29-006)
Discovered (May 1, 1834) by John Herschel (and later listed as NGC 4947)
Discovered (Mar 28, 1898) by Lewis Swift (and later listed as IC 3974)
A magnitude 11.9 spiral galaxy (type SAB(r)b pec) in Centaurus (RA 13 05 20.2, Dec -35 20 15)

Historical Identification: Per Dreyer, NGC 4947 (= GC 3388 = JH 3461, 1860 RA 12 57 34, NPD 124 35.1) is "faint, pretty large, round, very gradually a little brighter middle." (see IC 3974 for a discussion of the duplicate listing)
Physical Information: Apparent size 2.4 by 1.2 arcmin.

DSS image of region near spiral galaxy NGC 4947
Above, a 12 arcmin wide DSS image centered on NGC 4947
Below, a 3 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy NGC 4947

PGC 45180 (= PGC 651661 = ESO 382-004 = MCG -06-29-005A = "NGC 4947A")
Not an NGC object but listed here because sometimes called NGC 4947A
A 15th magnitude spiral galaxy (type SB(s)m?) in Centaurus (RA 13 04 20.8, Dec -35 13 40)

Physical Information: Apparent size 1.7 by 0.7 arcmin.

DSS image of region near spiral galaxy PGC 45180, also known as NGC 4947A
Above, a 12 arcmin wide DSS image centered on PGC 45180
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy PGC 45180, also known as NGC 4947A

NGC 4948 (probably = IC 4156) (= PGC 45224 = MCG -01-33-079)
Discovered (May 25, 1887) by Lewis Swift (and later listed as NGC 4948)
Discovered (July, 1899) by DeLisle Stewart (and later listed as IC 4156)
A magnitude 13.2 spiral galaxy (type SB(s)cd?) in Virgo (RA 13 04 56.0, Dec -07 56 52)

Historical Identification: Per Dreyer, NGC 4948 (Swift list VI (#51), 1860 RA 12 57 36, NPD 97 11.6) is "most extremely faint, pretty small, a little extended, I 130 following (to the east)," (WH) I 130 being NGC 4958. (See IC 4156 for a discussion of the probable duplicate listing)
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 1450 km/sec (and H0 = 70 km/sec/Mpc), NGC 4948 is about 65 to 70 million light-years away, in reasonable agreement with redshift-independent distance estimates of about 30 to 70 million light-years (though the median redshift-independent distance estimate of about 35 million light-years is considerably lower). Presuming a distance of about 65 to 70 million light-years, its apparent size of about 2.1 by 0.65 arcmin (from the images below) would make NGC 4948 about 40 thousand light-years across.
Since NGC 4948 has a recessional velocity essentially identical to that of PGC 45254, they are almost certainly a physical pair, and their distorted appearance is probably due to past interactions between them. Corwin states that deVaucouleurs put the pair in a group which includes NGC 4958 and PGC 45242
Classification Note: We are seeing NGC 4948 nearly edge-on, so unlike its probable companion, which is seen nearly face-on, its structure is not as obvious, nor as certain.

PanSTARRS image of region near spiral galaxy NGC 4948, also showing its probable companion, PGC 45254
Above, a 12 arcmin wide PanSTARRS image centered on NGC 4948, also showing PGC 45254
Below, a 2.5 by 2.75 arcmin wide PanSTARRS image of the galaxy
PanSTARRS image of spiral galaxy NGC 4948

PGC 45254 (= MCG -01-33-082)
Not an NGC object but listed here because almost certainly a physical companion of NGC 4948
A magnitude 16(?) spiral galaxy (type SB(rs)dm) in Virgo (RA 13 05 14.3, Dec -07 53 21)

Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 1450 km/sec (and H0 = 70 km/sec/Mpc), PGC 45254 is about 65 to 70 million light-years away, in good agreement with redshift-independent distance estimates of about 65 to 75 million light-years. Given that and its apparent size of about 2.8 by 1.5 arcmin (from the images below, counting the star clusters irregularly scattered beyond the obvious arms), the galaxy is about 55 thousand light-years across.
Since PGC 45254 has a recessional velocity essentially identical to that of NGC 4948, they are almost certainly a physical pair, and their distorted appearance is probably due to past interactions between them.

PanSTARRS image of region near spiral galaxy PGC 45254, also showing NGC 4948
Above, a 12 arcmin wide PanSTARRS image centered on PGC 45254, also showing NGC 4948
Below, a 3.75 arcmin wide PanSTARRS image of the galaxy
PanSTARRS image of spiral galaxy PGC 45254

PGC 45242 (MCG -01-33-080 = "NGC 4948A")
Not an NGC object but listed here because sometimes called NGC 4948A
A magnitude 13.5 spiral galaxy (type SB(s)dm) in Virgo (RA 13 05 05.7, Dec -08 09 39)

Physical Information: Apparent size 1.35 by 0.95 arcmin.

DSS image of region near spiral galaxy PGC 45242, also known as NGC 4948A
Above, a 12 arcmin wide DSS image centered on PGC 45242
Below, a 2.4 arcmin wide DSS image of the galaxy
DSS image of spiral galaxy PGC 45242, also known as NGC 4948A

NGC 4949 (= PGC 45161)
Discovered (Apr 19, 1865) by Heinrich d'Arrest
A magnitude 14.9 spiral galaxy (type SBb pec) in Coma Berenices (RA 13 04 17.9, Dec +29 01 46)

Historical Identification: Per Dreyer, NGC 4949 (= GC 5715, d'Arrest, 1860 RA 12 57 37, NPD 60 12.9) is "extremely faint, small."
Physical Information: Apparent size 0.6 by 0.3 arcmin.

SDSS image of region near spiral galaxy NGC 4949
Above, a 12 arcmin wide SDSS image centered on NGC 4949
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 4949
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