Celestial Atlas
(NGC 2350 - 2399) ←     NGC Objects: NGC 2400 - 2449     → (NGC 2450 - 2499)
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Last updated Nov 23, 2014
WORKING: Check for additional/better pix (if any)

NGC 2400
Recorded (Feb 26, 1853) by
George Bond
Three 14th and 15th magnitude stars in Canis Minor (RA 07 29 55.1, Dec -00 12 51)
Per Dreyer, NGC 2400 (= Bond (#10, HN 10), 1860 RA 07 22 46, NPD 89 55.7) is one of "two faint nebulae (Auwers 24 & 25), ? very small clusters", the other being NGC 2399. The position precesses to RA 07 29 56.0, Dec -00 12 55, within 0.2 arcmin of the triplet of stars, so the identification is certain. Note: A Wikisky search for NGC 2400 shows a region to the east of the triple star, and does not indicate any NGC label; so use the coordinates to see the correct object.
DSS image of region near  stellar groups NGC 2399 and 2400
Above, a 12 arcmin wide region centered on NGC 2400; also shown is the similar triple, NGC 2399

NGC 2401 (= OCL 588)
Discovered (Mar 8, 1793) by
William Herschel
A 13th-magnitude open cluster (type II3p) in Puppis (RA 07 29 24.3, Dec -13 58 00)
Per Dreyer, NGC 2401 (= John Herschel's GC 1539, 1860 RA 07 22 57, NPD 103 41.4) is "cluster, small, considerably rich, considerably compressed, stars very small". The position precesses to RA 07 29 24.4, Dec -13 58 35, about 0.6 arcmin south of the "standard" position, but well within the 2 or 3 arcmin diameter of the cluster, so the identification is certain. A 2006 study of the Hertzsprung-Russell Diagram of the cluster down to the 22nd magnitude yielded a distance of 20 thousand light years and an age of 25 million years, with its Main Sequence extending to B stars, and some indication that its lower mass stars might still be approaching the Main Sequence. This would make it among the youngest clusters in its region. Given its apparent size and distance, the cluster is between 12 and 16 light years in diameter.
SDSS image of open cluster NGC 2401
Above, a 4.8 arcmin wide SDSS closeup of NGC 2401
Below, a 12 arcmin wide region centered on the cluster
DSS image of region near open cluster NGC 2401

NGC 2402 (= PGC 21176 + PGC 200236)
Discovered (Mar 11, 1784) by
William Herschel
A pair of gravitationally interacting galaxies in Canis Minor
PGC 21176 is a 14th-magnitude elliptical galaxy (type E?) at RA 07 30 46.5, Dec +09 38 51
PGC 200236 is a 15th-magnitude spiral galaxy (type S) at RA 07 30 47.8, Dec +09 39 14
Per Dreyer, NGC 2402 (= John Herschel's GC 1540, 1860 RA 07 23 06, NPD 80 03.4) is "extremely faint, small, round, slightly brighter middle, star involved". The "star involved" could be either of the two stars between the two galaxies, but is probably the brighter one. The position precesses to RA 07 30 46.3, Dec +09 39 17, which agrees with the right ascension of the southwestern galaxy, and the declination of the northeastern one, so the identification is certain. The only question is whether Herschel (and later his son John) saw the combined light of both galaxies, or only that of the brighter one. Since the brighter star is closer to the fainter galaxy, its "involvement" suggests that they saw the entire grouping as a nebula and star; but the galaxies are a gravitationally interacting pair, so it seems appropriate to include both in any discussion of the NGC object whether the Herschels observed the light of both galaxies or only that of the brighter one. Based on a recessional velocity of 5300 km/sec, PGC 21176 is about 245 million light years away. Given that and its apparent size of 0.8 by 0.8 arcmin, it is about 55 thousand light years across. The fainter component, PGC 200236, has a recessional velocity of 5225 km/sec, but since peculiar (non-Hubble expansion) galaxy velocities are typically a hundred or more km/sec, the small difference in the galaxies' radial velocity says nothing about their relative distance, save that they must be almost as close in space as they appear in the sky. Even though the quality of the images below is not as good as might be desired, the brighter galaxy definitely shows some signs of gravitational distortion, so the two are probably separated by no more than a few hundred thousand light years. Given its apparent size of 0.8 by 0.5 arcmin, PGC 200236 is also about 55 thousand light years across. (Note: NGC 2402 is listed in NED simply as a pair; to access information about the individual galaxies, search for NGC 2402 NED01 and NGC 2402 NED02.)
DSS image of interacting galaxy pair NGC 2402
Above, a 2.4 arcmin wide closeup of NGC 2402
Below, a 12 arcmin wide region centered on the pair
DSS image of region near interacting galaxy pair NGC 2402

NGC 2403 (= PGC 21396)
Discovered (Nov 1, 1788) by
William Herschel
A 9th-magnitude spiral galaxy (type SAB(s)cd) in Camelopardalis (RA 07 36 50.6, Dec +65 36 06)
Per Dreyer, NGC 2403 (= John Herschel's GC 1541, 1860 RA 07 23 15, NPD 24 06.2) is "very remarkable, considerably bright, extremely large, very much extended, very gradually much brighter middle and nucleus". The position precesses to RA 07 36 48.9, Dec +65 35 54, about 0.4 arcmin southwest of the center of the galaxy, but well within its outline, so the identification is certain. NGC 2403's recessional velocity of 130 km/sec is too small in comparison to peculiar (non-Hubble-expansion) velocities to provide a reliable distance indicator. Redshift-independent distance estimates range from 9 to 21 million light years, with 11 million light years being the most generally accepted current value. Given that, the apparent size of 22 by 12 arcmin implies that the galaxy is about 70 thousand light years across. It contains a number of HII (emission) regions associated with various star clusters, one of which is an NGC object in its own right (NGC 2404). Used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type SAB(s)d.
SDSS image of spiral galaxy NGC 2403
Above, a 20 arcmin wide "closeup" of NGC 2403
Below, a view with different false-color choices (Credits: Fred Calvert/Adam Block/AURA/NSF/NOAO)
NOAO image of spiral galaxy NGC 2403
Below, a composite of SDSS and HST views of NGC 2403/4 (Image Credits: ESA, A.V. Filippenko (University of California, Berkeley), P. Challis (Harvard-Smithsonian Center for Astrophysics), et al., NASA)
Composite SDSS and HST image of central portion of spiral galaxy NGC 2403 and star-forming region NGC 2404
Below, the core of NGC 2403, and the emission region and open cluster NGC 2404 (Image Credits: ESA, A.V. Filippenko (University of California, Berkeley), P. Challis (Harvard-Smithsonian Center for Astrophysics), et al., NASA)
HST image of central portion of spiral galaxy NGC 2403 and star-forming region NGC 2404

NGC 2404
Discovered (Feb 2, 1886) by
Guillaume Bigourdan
An emission nebula and open cluster in NGC 2403 (RA 07 37 07.0, Dec +65 36 40)
Per Dreyer, NGC 2404 (= Bigourdan (list 1, #28), 1860 RA 07 23 28, NPD 24 00.0) is "very faint, very small". The position precesses to RA 07 37 03.6, Dec +65 42 03, almost 6 arcmin north of the correct position; but per Corwin, this is due to Dreyer's copying the incorrect position in Bigourdan's original paper. When Bigourdan published a massive compilation of all his discoveries he corrected the position, and the offsets he lists from reference stars agree with the corrected position, so the identification is certain. As shown in the images below, NGC 2404 is the largest and brightest emission nebula and "association" of hot bright stars in spiral galaxy NGC 2403. Given that galaxy's roughly 11 million light year distance, the approximately 0.3 arcmin apparent size of NGC 2404 suggests that it is about 1000 light years across. (Note: A Wikisky search for NGC 2404 shows the original incorrect NGC position, so use the coordinates above to see the correct region.)
SDSS image of spiral galaxy NGC 2403, showing the location of emission nebula and star-forming region NGC 2404
Above, a 20 arcmin wide "closeup" of NGC 2403; the box indicates the position of NGC 2404
Below, a view with different false-color choices (Image Credits: Fred Calvert/Adam Block/AURA/NSF/NOAO)
NOAO image of spiral galaxy NGC 2403, showing the location of emission nebula and star-forming region NGC 2404
Below, a composite of SDSS and HST views of NGC 2403/4 (Image Credits: ESA, A.V. Filippenko (University of California, Berkeley), P. Challis (Harvard-Smithsonian Center for Astrophysics), et al., NASA)
Composite SDSS and HST image of central portion of spiral galaxy NGC 2403 and star-forming region NGC 2404
Below, the HST closeup of the core of NGC 2403, showing NGC 2404 as well (Image credits as above)
HST image of central portion of spiral galaxy NGC 2403 and star-forming region NGC 2404

NGC 2405 (= PGC 21224)
Discovered (Nov 7, 1864) by
Albert Marth
A 14th-magnitude spiral galaxy (type Sc?) in Gemini (RA 07 32 13.9, Dec +25 54 22)
Per Dreyer, NGC 2405 (= Marth 105, 1860 RA 07 23 38, NPD 63 49) is "very faint, small, irregularly round". The position precesses to RA 07 32 13.0, Dec +25 53 29, about 0.9 arcmin southwest of the galaxy listed above. This is a larger than usual error for Marth, but there is nothing else nearby and no one seems to have raised any question about the identification, so it appears to be certain. Based on a recessional velocity of 5665 km/sec, NGC 2405 is about 265 million light years away. Given that and its apparent size of 0.45 by 0.35 arcmin, the galaxy is about 35 thousand light years across. Note: Steinicke lists the object as consisting of two components, a spiral galaxy and an elliptical galaxy, and in low resolution images there does appear to be an elliptical galaxy superimposed on the spiral; but the closeup below clearly shows that the superimposed object is a foreground star (namely, the lower star of the pair on the eastern side of the galaxy).
SDSS image of region near spiral galaxy NGC 2405
Above, a 12 arcmin wide SDSS image centered on NGC 2405
Below, a 2.4 arcmin wide SDSS image of the galaxy
SDSS image of spiral galaxy NGC 2405

NGC 2406 (= PGC 21218)
Discovered (Feb 7, 1885) by
Édouard Stephan
A 14th-magnitude elliptical galaxy (type E?) in Gemini (RA 07 31 47.7, Dec +18 17 19)
Per Dreyer, NGC 2406 (= Stephan's list XIII (#30), 1860 RA 07 23 40, NPD 71 25.3) is extremely faint, extremely small, very small nucleus?". The position precesses to RA 07 31 48.1, Dec +18 17 14, less than 0.2 arcmin southeast of the galaxy, so the identification is certain. Based on a recessional velocity of 13305 km/sec, a straightforward calculation indicates that NGC 2405 is about 620 million light years away; but for such distant objects we need to take into account the expansion of the Universe during the time it took the light of the object to reach us. Doing that shows that the galaxy was about 590 million light years away when the light by which we see it was emitted, about 600 million years ago (the difference between the two numbers being due to the expansion of the intervening space during that time). Given that and its apparent size of 0.85 by 0.65 arcmin, NGC 2406 is about 150 thousand light years across. The galaxy is a Seyfert galaxy (type Sy 2); this may be the reason Stephan thought it had a very small nucleus.
SDSS image of elliptical galaxy NGC 2406
Above, a 2.4 arcmin wide closeup of NGC 2406
Below, a 12 arcmin wide region centered on the galaxy; also shown is NGC 2407
SDSS image of region near elliptical galaxy NGC 2406, also showing lenticular galaxy NGC 2407

NGC 2407 (= PGC 21220)
Discovered (Feb 7, 1885) by
Édouard Stephan
A 13th-magnitude lenticular galaxy (type E/S0?) in Gemini (RA 07 31 56.6, Dec +18 20 01)
Per Dreyer, NGC 2407 (= Stephan's list XIII (#31), 1860 07 23 49, NPD 71 22.5) is "extremely faint, extremely small, very small nucleus?". The position precesses to RA 07 31 57.3, Dec +18 20 00, less than 0.2 arcmin east of the center of the galaxy, so the identification is certain. Based on a recessional velocity of 3530 km/sec, NGC 2407 is about 165 million light years away. Given that and its apparent size of 0.95 by 0.85 arcmin, it is about 45 thousand light years across. As in the case of NGC 2406, NGC 2407 displays a bright core which may explain Stephan's reference to a possible nucleus; but there has been no suggestion that this galaxy might be a Seyfert galaxy.
SDSS image of lenticular galaxy NGC 2407
Above, a 2.4 arcmin wide closeup of NGC 2407
Below, a 12 arcmin wide region centered on the galaxy; also shown is NGC 2406 (The image had considerable glare due to an 8th-magnitude star to the left of the field of view; this was removed by superimposing a small DSS cutout)
SDSS image of region near lenticular galaxy NGC 2407, using a DSS cutout to remove glare from a nearby star; also shown is elliptical galaxy NGC 2406

NGC 2408
Discovered (January 1830) by
John Herschel
A group of stars in Camelopardalis (RA 07 40 30.0, Dec +71 40 00)
Per Dreyer, NGC 2408 (= John Herschel's GC 1542, 1860 RA 07 24 36, NPD 18 01.6) is "cluster, very slightly compressed". The position precesses to RA 07 40 30.2, Dec +71 40 01, dead center on the position listed above, so the identification is certain. Per Corwin, the group is probably an irregular fluctuation in the general star field. He states that about two dozen stars of greater than average brightness are scattered over a roughly 25 arcmin wide region centered on the bright star taken as its center by Herschel. Similarly, Gottlieb states that about 50 stars are scattered across a roughly 20 arcmin wide region. I have seen some references that list the group as being only about 10 arcmin in size, but as shown by the images below there is no sign of the group at the smaller size, so the 20+ arcmin size quoted by Corwin and Gottlieb seems a far better estimate (it also better fits the "very slightly compressed" description from the original NGC). Note: A Wikisky search for NGC 2408 shows the correct region, but at such a high magnification that it is impossible to tell what is being shown; so a search using the coordinates is recommended.
DSS image of 'smaller version' of star group NGC 2408
Above, a 12 arcmin wide region centered on NGC 2408 shows no concentration of stars
Below, a 24 arcmin wide region with the same center shows a loosely scattered grouping
DSS image of region near star group NGC 2408

NGC 2409
Discovered (Feb 12, 1836) by
John Herschel
A 7th-magnitude open cluster in Puppis (RA 07 31 36.7, Dec -17 11 23)
Per Dreyer, NGC 2409 (= John Herschel's GC 1543, 1860 RA 07 25 22, NPD 106 54.3) is a "cluster, small but bright, stars from 8th to 10th magnitude". The position precesses to RA 07 31 39.1, Dec -17 11 55, dead center on the group's brightest members, so the identification seems certain. The group is only 2.5 arcmin across, and makes a striking concentration; but given the small number of stars (only 8 or 9) cannot be a true cluster (such a small group would be quickly disrupted by the gravitational effects of passing stars as it orbits the galaxy). Note: A Wikisky search for NGC 2409 shows the correct region, but does not provide any label indicating what, if anything, is the NGC object.
DSS image of open cluster NGC 2409
Above, a 6 arcmin wide region centered on NGC 2409
Below, a 12 arcmin wide region centered on the asterism
DSS image of region near open cluster NGC 2409
Below, a 45 arcmin wide region centered on the asterism, also showing a faint emission
and reflection nebula, Sharpless 2-302, which is probably unrelated to the asterism
DSS image of region near open cluster NGC 2409, also showing the emission and reflection nebula Sharpless 2-302

NGC 2410 (= PGC 21336)
Discovered (Feb 5, 1867) by
Truman Safford
Rediscovered (Feb 2, 1877) by Édouard Stephan (as credited by Dreyer)
A 13th-magnitude spiral galaxy (type SBb?) in Gemini (RA 07 35 02.2, Dec +32 49 21)
Per Dreyer, NGC 2410 (= Stephan's list VIII, 1860 RA 07 26 00, NPD 56 52.6) is "extremely faint, very small, several very faint stars involved". The second IC adds "= Javelle 1005, faint, extended 250°, 1 arcmin long, gradually brighter middle, mottled but not resolved". There is also a note in the Appendix to the NGC, stating that an overlooked list by Truman Safford included 106 nebulae, fifty-nine of which had already been listed in the NGC with attribution to other individuals. Unfortunately, the Appendix only lists those objects that Safford discovered which had not yet been listed in the NGC; so where he had the right of prior discovery, it was not noted. However, per Steinicke, NGC 2410 is Safford #74, one of the fifty-nine objects for which Safford deserved credit for the original discovery. The position precesses to RA 07 35 02.3, Dec +32 49 24, dead center on the galaxy, so the identification is certain. Based on a recessional velocity of 4680 km/sec, NGC 2410 is about 220 million light years away, in reasonable agreement with redshift-independent distance estimates of 205 to 210 million light years. Given that and its 2.35 by 0.7 arcmin apparent size, it is about 150 thousand light years across. The galaxy is listed as a Seyfert galaxy (type Sy 2).
SDSS image of spiral galaxy NGC 2410
Above, a 2.4 arcmin wide region centered on NGC 2410
Below, a 12 arcmin wide region centered on the galaxy
SDSS image of region near spiral galaxy NGC 2410

NGC 2411 (= PGC 21315)
Discovered (Feb 7, 1885) by
Édouard Stephan
A 14th-magnitude elliptical galaxy (type E4?) in Gemini (RA 07 34 36.4, Dec +18 16 55)
Per Dreyer, NGC 2411 (= Stephan's list XIII (#32), 1860 RA 07 26 29, NPD 71 25.1) is "14th-magnitude star, slightly nebulous". The position precesses to RA 07 34 36.8, Dec +18 16 54, within 0.1 arcmin of the center of the galaxy, so the identification is certain. Based on a recessional velocity of 5075 km/sec, NGC 2411 is about 235 million light years away. Given that and its apparent size of 1.1 by 0.65 arcmin, it is about 75 thousand light years across.
SDSS image of elliptical galaxy NGC 2411
Above, a 2.4 arcmin wide region centered on NGC 2411; also shown is PGC 1555546
Below, a 12 arcmin wide region centered on the galaxy
SDSS image of region near elliptical galaxy NGC 2411

NGC 2412
Recorded (1886) by
Gerhard Lohse
A double star (13th and 14th magnitude) in Canis Minor (RA 07 34 21.5, Dec +08 32 51)
Per Dreyer, NGC 2412 (= J. G. Lohse, 1860 RA 07 26 45, NPD 81 09.4) is "very faint, 8th-magnitude star 59 arcsec and 1.5 seconds of time to the southeast, 13th-magnitude star 10 arcsec away". The position precesses to RA 07 34 21.7, Dec +08 32 36, right on the southern member of the pair, so the identification is certain. As noted by Corwin, such close doubles are easily confused with nebulous objects in normal observing conditions, so it is not surprising that Lohse mistook the pair for a nebula.
DSS image of region near the pair of stars listed as NGC 2412
Above, a 12 arcmin wide region centered on "NGC 2412"

NGC 2413
Discovered (Mar 19, 1786) by
William Herschel
A loose group of stars in Puppis (RA 07 33 19.0, Dec -13 07 09)
Per Dreyer, NGC 2413 (= John Herschel's GC 1544, 1860 RA 07 26 50, NPD 102 47.8) is a "cluster, very large, poor, very slightly compressed". The position precesses to RA 07 33 20.5, Dec -13 05 43, about 1.5 arcmin northeast of the star (9th magnitude HD 60307) taken as the center of the group by Herschel, but well within the 12 to 15 arcmin wide region containing the "cluster". Most observers agree that this is not a true cluster, but merely an accidental concentration of the general star field consisting of two loose groups of stars lying to the north and south of the "central" star. Note: A Wikisky search for NGC 2413 centers on a region to the northeast of the cluster, and no label is shown to indicate its identity; so a search should be based on the listed coordinates.
DSS image of region near the group of stars listed as NGC 2413
Above, a 15 arcmin wide region centered on "NGC 2413"

NGC 2414 (= OCL 598)
Discovered (Feb 4, 1785) by
William Herschel
An 8th-magnitude open cluster (type I3m) in Puppis (RA 07 33 12.8, Dec -15 27 14)
Per Dreyer, NGC 2414 (= John Herschel's GC 1545, 1860 RA 07 26 50, NPD 105 08.8) is a "cluster, poor, slightly compressed, stars 9th-magnitude etc". The position precesses to RA 07 33 13.0, Dec -15 26 42, about 0.5 arcmin north of the center of the cluster; but given the cluster's size and the difficulty of determining the center of an open cluster, the position might as well be dead center, and the identification is certain. The group consists of several arcs of faint stars spread across a 5 to 6 arcmin wide region centered on 8th magnitude star HD 60308. Fewer than two dozen stars stand out from the general background, and how many of the fainter background stars are associated with the group is unknown.
DSS image of open cluster NGC 2414
Above, a 12 arcmin wide region centered on NGC 2414

NGC 2415 (= PGC 21399)
Discovered (Mar 10, 1790) by
William Herschel
A 12th-magnitude irregular galaxy (type Im?) in Gemini (RA 07 36 56.5, Dec +35 14 31)
Per Dreyer, NGC 2415 (= John Herschel's GC 1546, 1860 RA 07 27 43, NPD 54 28.4) is "pretty bright, considerably small, round, very gradually very slightly brighter middle, mottled but not resolved, almost planetary nebular". The position precesses to RA 07 36 55.5, Dec +35 13 16, over a minute of arc to the south of the galaxy, but there is nothing else nearby, and the "almost planetary nebular" appearance certainly fits the appearance of the galaxy, so the identification seems certain. Based on a recessional velocity of 3785 km/sec, NGC 2415 is about 175 million light years away. Given that and its apparent size of 0.9 by 0.9 arcmin, it is about 45 thousand light years across.
SDSS image of irregular galaxy NGC 2415
Above, a 2.4 arcmin wide closeup of NGC 2415
Below, a 12 arcmin wide region centered on the galaxy
SDSS image of region near irregular galaxy NGC 2415

NGC 2416 (= PGC 21358)
Discovered (Jan 26, 1865) by
Albert Marth
A 13th-magnitude spiral galaxy (type Scd?) in Canis Minor (RA 07 35 41.4, Dec +11 36 45)
Per Dreyer, NGC 2416 (= Marth 106, 1860 RA 07 28 05, NPD 78 06) is "extremely faint, small". The position precesses to RA 07 35 51.1, Dec +11 35 44, about 2.6 arcmin to the southeast of the galaxy. Even for Marth, who often made errors of an arcmin or so (per Steinicke, because the 48" equatorial refractor he used was very cumbersome to handle), a 2.6 arcmin error is unusually large; but there is nothing else nearby, and no one seems to have ever expressed any concern about the identification, so it must be presumed reasonably certain. Based on a recessional velocity of 5100 km/sec, NGC 2416 is about 235 million light years away, somewhat further than redshift-independent distance estimates of 180 to 195 million light years. Using an intermediate distance of about 200 million light years, its 1.0 by 0.7 arcmin apparent size would suggest that the galaxy is about 60 thousand light years across.
DSS image of spiral galaxy NGC 2416
Above, a 2.4 arcmin wide closeup of NGC 2416
Below, a 12 arcmin wide region centered on the galaxy
DSS image of region near spiral galaxy NGC 2416

NGC 2417 (= PGC 21155)
Discovered (Mar 8, 1836) by
John Herschel
A 12th-magnitude spiral galaxy (type SA(rs)bc) in Carina (RA 07 30 12.1, Dec -62 15 09)
Per Dreyer, NGC 2417 (= John Herschel's GC 1547, 1860 RA 07 28 25, NPD 151 57.8) is "very faint, large, round, gradually brighter middle, mottled but not resolved". The position precesses to RA 07 30 08.2, Dec -62 15 34, a little over 1 arcmin southwest of the center of the galaxy, but within its outline, so there has never been any doubt of the identification. Based on a recessional velocity of 3210 km/sec, NGC 2417 is about 150 million light years away, in good agreement with redshift-independent distance estimates of 110 to 170 million light years. Given that and its apparent size of 2.8 by 1.9 arcmin, the galaxy is about 120 thousand light years across.
DSS image of spiral galaxy NGC 2417
Above, a 3 arcmin wide closeup of NGC 2417
Below, a 12 arcmin wide region centered on the galaxy
DSS image of region near spiral galaxy NGC 2417

NGC 2418 (= PGC 21382 = Arp 165)
Discovered (Jan 23, 1874) by
Édouard Stephan
A 12th-magnitude elliptical galaxy (type E0?) in Gemini (RA 07 36 37.4, Dec +17 53 02)
Per Dreyer, NGC 2418 (= Stephan's list VIII (#21), 1860 RA 07 28 31, NPD 71 48.6) is "very faint, extremely small, brighter middle". The position precesses to RA 07 36 37.3, Dec +17 53 01, dead center on the galaxy, so the identification is certain. Based on a recessional velocity of 5035 km/sec, NGC 2418 is about 235 million light years away. Given that and its apparent size of 1.8 by 1.8 arcmin, it is about 120 thousand light years across. The galaxy exhibits some distortion to the north, and considerable distortion to the southeast.
SDSS image of elliptical galaxy NGC 2418
Above, a 3.6 arcmin wide closeup of NGC 2418, showing distortion to the north and southeast
Below, a 12 arcmin wide region centered on the galaxy
SDSS image of region near elliptical galaxy NGC 2418

NGC 2419 (= PGC 2802643 = GCL 12), the Intergalactic Wanderer
Discovered (Dec 31, 1788) by
William Herschel
A 10th-magnitude globular cluster (type II) in Lynx (RA 07 38 08.5, Dec +38 52 57)
Per Dreyer, NGC 2419 (= John Herschel's GC 1548, 1860 RA 07 28 39, NPD 50 48.6) is "pretty bright, pretty large, slightly extended 90°, very gradually brighter middle, 7th or 8th magnitude star 4 arcmin distant in direction 267°". The position precesses to RA 07 38 08.5, Dec +38 52 52, almost dead center on the cluster, and there is a bright star just to the west, as shown in the wide-field image below; so the identification is certain. NGC 2419 is one of the most distant globular clusters in our galaxy; in fact, until recently it was thought that it might not be a permanent part of our halo at all, and was referred to as "The Intergalactic Wanderer". However, it is now believed that it is orbiting the Milky Way, though in a path which takes it beyond the Magellanic Clouds (it is currently nearly twice as far away as the Large Magellanic Cloud), with an orbital period of around 3 billion years. Based on it and the Sun's relative locations, NGC 2419 is about 275 thousand light years from the Sun and 300 thousand light years from the galactic center. Given that and its apparent size of nearly 5 arcmin, it is about 400 light years across, making it nearly three times the diameter and thirty times the volume of the next largest Milky Way globular, Omega Centauri. Omega Centauri contains ten to fifteen million Solar masses, so if NGC 2419 has a similar density, it could have a mass of three or four hundred million Solar masses, more than that of many "dwarf" galaxies. Even if its concentration of stars is considerably less, it must have the best part of a hundred million Solar masses, and far outstrip any other Milky Way globular in every respect. If it were as close as Omega Centauri, it would be a 3rd-magnitude fuzzball nearly two degrees in diameter, and as easily visible to the unaided eye as the Magellanic Clouds; and since it lies north of the Celestial Equator, would be one of the most spectacular objects in the northern sky.
SDSS image of globular cluster NGC 2419
Above, a 6 arcmin wide closeup of NGC 2419
Below, a 12 arcmin wide region centered on the globular cluster
SDSS image of region near globular cluster NGC 2419

NGC 2420 (= OCL 488)
Discovered (Nov 19, 1783) by
William Herschel
An 8th-magnitude open cluster (type I2r) in Gemini (RA 07 38 23.8, Dec +21 34 27)
Per Dreyer, NGC 2420 (= John Herschel's GC 1549, 1860 RA 07 30 06, NPD 68 07.2) is a "cluster, considerably large, rich, compressed, stars from 11th to 18th magnitude". The position precesses to RA 07 38 24.6, Dec +21 34 06, about 0.4 arcmin southeast of the center of the cluster; but in comparison to the size of the cluster and the difficulty of determining its center, the position can be considered to be dead on, and the identification is certain. NGC 2420 is a group of nearly a thousand stars located about 6500 light years from the Sun. Its superficial appearance is of a central core about 6 arcmin in diameter, with a considerable scattering of stars to about twice that distance; but a detailed study of stars in the neighborhood of the cluster indicates that some members are nearly 20 arcmin from the center, which would correspond to an overall size of nearly 75 light years, and since the tidal radius of the cluster is even greater than that, the actual number of cluster stars may be considerably larger than the estimate above. However, at least half the mass of the cluster is within 4.5 arcmin of its center, so the "smaller" view does show the most visible cluster members.
DSS image of central portion of open cluster NGC 2420
Above, a 12 arcmin wide region centered on NGC 2420, showing a little over half its members
Below, a 40 arcmin wide region centered on the cluster, presumably showing all cluster members
DSS image of central portion of region near open cluster NGC 2420

NGC 2421 (= OCL 626)
Discovered (Jan 30, 1799) by
William Herschel
An 8th-magnitude open cluster (type I2m) in Puppis (RA 07 36 12.0, Dec -20 36 42)
Per Dreyer, NGC 2421 (= John Herschel's GC 1550, 1860 RA 07 30 10, NPD 110 18.0) is a "cluster, large, considerably rich, stars from 11th to 13th magnitude". The position precesses to RA 07 36 16.1, Dec -20 36 30, about 1 arcmin north of the "center" of the cluster, but between the size of the cluster and the difficulty of saying where the center is, the position is essentially dead on, and the identification is certain. NGC 2421 is a group of several hundred stars about 7000 light years from the Sun. The main portion of the cluster is about 6 arcmin in diameter, but the numerous field stars make it difficult to tell its true extent, or which stars are cluster members and which are not. Still, a photometric study of the cluster has been carried out which indicates that it is only about 80 million years old, making it one of the youngest clusters known.
DSS image of region near open cluster NGC 2421
Above, a 12 arcmin wide region centered on NGC 2421

NGC 2422 (=
M47 = NGC 2478 = OCL 596)
Discovered (before 1654) by Giovanni Hodierna
Discovered (Feb 19, 1771) but misrecorded by Charles Messier (and later listed as NGC 2478)
Discovered (early 1783) by Caroline Herschel
Discovered (Feb 4, 1785) by William Herschel (and later listed as NGC 2422)
A 4th-magnitude open cluster (type III2m) in Puppis (RA 07 36 35.0, Dec -14 28 47)
Per Dreyer, NGC 2422 (= John Herschel's GC 1551, 1860 RA 07 30 11, NPD 104 10.5) is a "cluster, bright, very large, pretty rich, stars large and small". The position precesses to RA 07 36 37.4, Dec -14 29 03, about 0.7 arcmin southeast of the center of the cluster; but for an open cluster, between its size and the difficulty of defining a center, this is essentially dead on, and the identification is certain. As far as the obviously complex credit for discovery goes, see the note about Hodierna for an explanation of why none of his observations resulted in an NGC listing. Messier's discovery went unnoticed because he made an error in the calculation of the position which resulted in his being given credit for a nonexistent object which was not recognized as being the same as NGC 2422 until 1959 (see NGC 2478). Given that, by all rights Caroline Herschel should have received contemporary credit for the discovery; but when her brother William rediscovered the object and added it to his catalog, that record resulted in his receiving the credit for the discovery. NGC 2422 consists of about 50 fairly bright stars spread across a region about half a degree in diameter. At its estimated distance of 1600 light years, this corresponds to a physical diameter of about 15 light years. The hottest Main Sequence star in the cluster is of spectral type B2; this suggests an age for the cluster of about 80 million years. As shown in the wide-field image below, there are several open clusters in Puppis that are in the same general area.
NOAO image of open cluster NGC 2422, also known as M47
Above, a 40 arcmin wide true-color image centered on the cluster (Image Credits: AURA/NSF/NOAO)
Below, a 2 degree wide region showing clusters M46, M47, NGC 2423 and 2425
Also shown are planetary nebula NGC 2438 and at the bottom, the 5th magnitude star HD 61772
DSS image of region in Puppis containing the open clusters M46 (also known as NGC 2437), M47 (also known as NGC 2422), NGC 2423 and 2425, and planetary nebula NGC 2438
The image above is centered at RA 07 39 00, Dec -14 22 00

NGC 2423 (= OCL 592)
Discovered (Mar 19, 1786) by
William Herschel
A 7th-magnitude open cluster (type IV2m) in Puppis (RA 07 37 06.7, Dec -13 52 17)
Per Dreyer, NGC 2423 (= John Herschel's GC 1552, 1860 RA 07 30 38, NPD 103 32.9) is a "cluster, very large, rich, pretty compressed, stars very small". The position precesses to RA 07 37 06.4, Dec -13 51 32, within 0.8 arcmin of the center of the cluster, which as noted for other open clusters, is essentially dead on, so the identification is certain. NGC 2423 is a loose collection of 50 to 60 faint stars spread across a region nearly 20 arcmin wide, lying about 2500 light years from the Sun. Given the distance and apparent size of the cluster, it has a diameter of about 15 light years.
DSS image of region near open cluster NGC 2423
Above, a 30 arcmin wide region centered on the cluster; also see the wide field image of NGC 2422

NGC 2424 (= PGC 21558 = PGC 3129334)
Discovered (Feb 6, 1885) by
Édouard Stephan
A 13th-magnitude spiral galaxy (type SB(r)b?) in Lynx (RA 07 40 39.3, Dec +39 14 00)
Per Dreyer, NGC 2424 (= Stephan's list XIII (#33), 1860 RA 07 31 09, NPD 50 27.0) is "very faint, pretty small, much extended, slightly brightly middle, mottled but not resolved?". The position precesses to RA 07 40 39.6, Dec +39 13 59, dead center on the galaxy, so the identification is certain. Based on a recessional velocity of 3355 km/sec, NGC 2424 is about 155 million light years away, in good agreement with redshift-independent distance estimates of 155 to 165 million light years. Given that and its apparent size of 3.5 by 0.55 arcmin, it is about 160 thousand light years across. The edge-on orientation of the galaxy, even though it agrees with Dreyer's note "much extended", makes accurate classification of the galaxy difficult; hence the question mark about its type.
SDSS image of spiral galaxy NGC 2424
Above, a 4 arcmin wide closeup of NGC 2424
Below, a 12 arcmin wide region centered on the galaxy
SDSS image of region near spiral galaxy NGC 2424

NGC 2425 (= OCL 599)
Discovered (Mar 8, 1793) by
William Herschel
An open cluster (type III2p) in Puppis (RA 07 38 17.6, Dec -14 52 40)
Per Dreyer, NGC 2425 (= John Herschel's GC 1553, 1860 RA 07 31 52, NPD 104 35.2) is a "cluster, poor, small, stars very small". The position precesses to RA 07 38 17.2, Dec -14 54 03, about 1.4 arcmin south of the "current" center of the cluster; but as for all such clusters, such an "error" is insignificant, and the identification is certain. NGC 2425 appears to consist of about three dozen stars located about 11 thousand light years from the Sun (this estimate only represents the brighter, more obvious cluster members; there may be far more fainter ones, which do not stand out against the starry background). Given that and its apparent size of 4 arcmin, it is about 13 light years in diameter. Studies of its Hertzsprung-Russell Diagram suggest that it is between 2 and 2.5 billion years old.
DSS image of open cluster NGC 2425
Above, a 6 arcmin wide region centered on the cluster; also see the wide field image of NGC 2422

NGC 2426 (= PGC 21648)
Discovered (Mar 10, 1790) by
William Herschel
A 13th-magnitude elliptical galaxy (type E0?) in Lynx (RA 07 43 18.4, Dec +52 19 05)
Per Dreyer, NGC 2426 (= John Herschel's GC 1554, 1860 RA 07 32 27, NPD 37 20.8) is "considerably faint, round, very gradually brighter middle, mottled but not resolved, 8th-magnitude star to west". The position precesses to RA 07 43 19.1, Dec +52 19 49, about 0.7 arcmin north of the center of the galaxy, but close to its outer glow, and 8th-magnitude HD 233440 does lie directly to the west, so the identification is certain. Based on a recessional velocity of 5675 km/sec, NGC 2426 is about 265 million light years away. Given that and its apparent size of 1.1 by 1.1 arcmin, it is about 85 thousand light years across.
DSS image of elliptical galaxy NGC 2426
Above, a 2.4 arcmin wide closeup of NGC 2426
Below, a 12 arcmin wide region centered on the galaxy; also shown are NGC 2429 and 2429B
DSS image of region near elliptical galaxy NGC 2426, also showing spiral galaxy NGC 2429 and its companion

NGC 2427 (= PGC 21375)
Discovered (Mar 1, 1835) by
John Herschel
A 12th-magnitude spiral galaxy (type SAB(s)c pec) in Puppis (RA 07 36 27.9, Dec -47 38 09)
Per Dreyer, NGC 2427 (= John Herschel's GC 1555, 1860 RA 07 32 32, NPD 173 18.5) is "extremely faint, large, pretty much extended, gradually much brighter middle, 2 stars involved". The position precesses to RA 07 36 35.4, Dec -47 37 15, about 2 arcmin to the northeast of the center of the galaxy, but close to its very large outline, so the identification is certain. Based on a recessional velocity of 970 km/sec, NGC 2427 is about 45 million light years away, in good agreement with redshift-independent distance estimates of 35 to 45 million light years. Given that and its apparent size of 5.2 by 2.2 arcmin, the galaxy is about 65 thousand light years across.
DSS image of spiral galaxy NGC 2427
Above, a 6 arcmin wide closeup of NGC 2427
Below, a 12 arcmin wide region centered on the galaxy
DSS image of region near spiral galaxy NGC 2427

NGC 2428
Discovered (Dec 31, 1785) by
William Herschel
A 12th-magnitude open cluster in Puppis (RA 07 39 22.0, Dec -16 31 42)
Per Dreyer, NGC 2428 (= John Herschel's GC 1556, 1860 RA 07 32 56, NPD 106 11.8) is a "cluster, very large, very slightly compressed". The position precesses to RA 07 39 16.1, Dec -16 30 51, about 1.7 arcmin northwest of the center of the cluster, but in comparison to the size of the cluster and the difficulty of determining its center, this is an insignificant error, so the identification is certain. Barely distinguishable from the background stars around it, NGC 2428 is a loose scattering of stars 6 to 12 arcmin across. The group is thought to be about 7000 light years away, in which case its apparent size corresponds to a physical diameter of 10 to 20 light years. Note: A Wikisky search for NGC 2428 shows the correct region, but does not display the NGC listing.
DSS image of open cluster NGC 2428
Above, a 12 arcmin wide view of NGC 2428

NGC 2429 (= PGC 21664)
Discovered (Mar 10, 1874) by
Ralph Copeland
A 14th-magnitude spiral galaxy (type Sbc pec?) in Lynx (RA 07 43 47.5, Dec +52 21 27)
Per Dreyer, NGC 2429 (= Copeland, using Lord Rosse's Leviathan, 1860 RA 07 32 56, NPD 37 18.6) is "pretty faint, pretty small, very much extended, 12th magnitude star attached". The position precesses to RA 07 43 48.2, Dec +52 21 56, about 0.5 arcmin north of the galaxy, but close enough to be certain of the identification. The galaxy and its fainter southeastern companion (2429B) are obviously distorted and must be a gravitationally interacting pair. Based on a recessional velocity of 5450 km/sec, NGC 2429 is about 250 million light years away. Given that and its apparent size of 1.7 by 0.35 arcmin, it is about 125 thousand light years across. Note: Although a Wikisky search shows the correct object, it labels it as NGC 2429A. Insofar as this is used only to distinguish it from NGC 2429B, the label is reasonable; but often, such a label is used to refer to a completely different galaxy, so its use should probably be discouraged.
DSS image of peculiar spiral galaxy NGC 2429 and its lenticular companion, NGC 2429B
Above, a 2.4 arcmin wide closeup of NGC 2429 and NGC 2429B
Below, a 12 arcmin wide region centered on the galaxy; also shown is NGC 2426
DSS image of region near peculiar spiral galaxy NGC 2429 and its lenticular companion, NGC 2429B, also showing elliptical galaxy NGC 2426

NGC 2429B (= PGC 21663)
A 17th-magnitude lenticular galaxy (type E/S0 pec?) in
Lynx (RA 07 43 51.8, Dec +52 20 53)
No recessional velocity is listed for NGC 2429B, but it and its brighter northwestern companion (NGC 2429, which see for images) are obviously distorted and must be a gravitationally interacting pair, so "B" must also be about 250 million light years away. Given that and its apparent size of 0.4 by 0.2 arcmin, it is about 30 thousand light years across.

NGC 2430
Discovered (Dec 31, 1785) by
William Herschel
A group of stars in Puppis (RA 07 39 41.0, Dec -16 17 46 ?)
Per Dreyer, NGC 2430 (= John Herschel's GC 1557, 1860 RA 07 33 05, NPD 106 01.8) is a "cluster, very large, very slightly compressed". The position precesses to RA 07 39 25.6, Dec -16 20 53, about 5 arcmin southwest of the position listed above. As shown in the images below, there is little to choose between the two positions. Both images show a sparse group of moderately bright stars scattered across a 12 to 15 arcmin wide region, which are probably little more than an accidental enhancement of the starry background. Neither view gives any great impression of an actual cluster of stars, and for that reason many catalogs don't bother to list NGC 2430 as a cluster. However, Corwin feels that the region 5 arcmin to the northeast of Herschel's position looks a little more like Herschel's description than the region centered on Dreyer's precessed position; and Steinicke, agreeing with Corwin, has based the position for the cluster on that opinion. My own view is that what Herschel saw was somewhere in the region shown by the images, but whether it was at the position measured by him or the one suggested by Corwin (or some completely different position) cannot be determined with any confidence, hence my decision to place a question mark after Steinicke's position. Note: Although a Wikisky search for NGC 2430 shows the more or less correct region (depending upon which region you think is the correct one), it does not indicate the NGC listing; but given the uncertainty of the identification, perhaps that is appropriate.
DSS image centered on Herschel and Dreyer's position for stellar group NGC 2430
Above, an 18 arcmin wide region centered on Herschel and Dreyer's position for NGC 2430
Below, an 18 arcmin wide region centered on Corwin and Steinicke's postion for the group
DSS image centered on Corwin and Steinicke's position for stellar group NGC 2430

NGC 2431 (= PGC 21711, and probably =
NGC 2436)
Discovered (Mar 17, 1790) by William Herschel (and later listed as NGC 2431)
Discovered (Feb 16, 1831) by John Herschel (and later listed as NGC 2436)
A 13th-magnitude spiral galaxy (type (R')SB(s)a) in Lynx (RA 07 45 13.3, Dec +53 04 32)
Per Dreyer, NGC 2431 (= John Herschel's GC 1558, 1860 RA 07 34 27, NPD 36 35.0) is "extremely faint, very small, round, brighter middle". The position precesses to RA 07 45 24.4, Dec +53 05 15, almost 3 arcmin northeast of the center of the galaxy; but there is nothing else nearby, so the identification is reasonably certain. (See NGC 2436 for a discussion of the double listing.) Based on a recessional velocity of 5680 km/sec, NGC 2431 is about 265 million light years away. Given that and its apparent size of 0.9 by 0.9 arcmin, it is about 70 thousand light years across.
DSS image of spiral galaxy NGC 2431
Above, a 2.4 arcmin wide closeup of NGC 2431
Below, a 12 arcmin wide region centered on the galaxy
DSS image of region near spiral galaxy NGC 2431

NGC 2432 (= OCL 620)
Discovered (Mar 4, 1790) by
William Herschel
A 10th-magnitude open cluster (type II1p) in Puppis (RA 07 40 53.0, Dec -19 04 36)
Per Dreyer, NGC 2432 (= John Herschel's GC 1559, 1860 RA 07 34 42, NPD 108 45.6) is a "cluster, pretty large, pretty compressed, extended 0°, stars large and small". The position precesses to RA 07 40 53.8, Dec -19 04 58, about 0.4 arcmin northeast of the center of the cluster; and given the difficulty of determining the center of such objects, such a small "error" means the identification is certain. The cluster consists of a few dozen stars scattered across a 6 to 8 arcmin wide region, but the majority of the stars are in a north-south arc about 5 arcmin high and 2 arcmin wide. A color-magnitude analysis of the central region of NGC 2432 indicates that it is between 4500 and 8500 light years away, which would make the region studied about 8 to 10 light years in diameter, and the entire cluster about 12 to 15 light years across. Based on the turnoff point for the Main Sequence, the age of the cluster is estimated at 200 million years. Note: A Wikisky search for NGC 2432 shows and labels a region nearly 4 arcmin to the southeast; so it is better to use the coordinates to do a search.
DSS image of open cluster NGC 2432
Above, a 12 arcmin wide region centered on NGC 2432

NGC 2433 (= PGC 3325911)
Recorded (Jan 19, 1828) by
John Herschel
A 12th-magnitude triple star in Canis Minor (RA 07 42 43.6, Dec +09 15 33)
Per Dreyer, NGC 2433 (= John Herschel's GC 1560, 1860 RA 07 35 05, NPD 80 24.8) is "extremely faint, with a 15th-magnitude star 90 arcsec to the southwest". A note at the end of the original NGC questions whether Herschel's measurement is correct, or a different one by d'Arrest; however, the first IC adds (per Spitaler) "Herschel's RA is correct". The position precesses to RA 07 42 43.5, Dec +09 15 38, dead on the position of the triple star, and there is a 15th-magnitude (fairly wide) double star to the southwest, so the identification is certain. Despite this there is considerable confusion about the identification of NGC 2433. LEDA lists the object as a nonexistent galaxy at the same position as the triple star (hence the PGC entry for it), while a Wikisky search for NGC 2433 shows a galaxy, but at a completely different location (RA 07 42 56.9, Dec 09 20 52), and with (by necessity) a completely different identification (PGC 21634). Corwin states that LEDA misidentifies the object as a faint galaxy to the northeast (which may be the reason for Wikisky's error), but as stated above, although LEDA misidentifies the object as a galaxy, it does use the position of the triple star. Since different references may give different identifications for the object, a search for NGC 2433 should use the coordinates listed above for the triple star.
DSS image of the triple star listed as NGC 2433
Above, a 6 arcmin wide region centered on the triple star
Below, a 12 arcmin wide region centered on the triplet, also showing IC 473 and PGC 21634
DSS image of region near the triple star listed as NGC 2433, also showing spiral galaxy PGC 21634, which is sometimes misidentified as NGC 2433, and the double star listed as IC 473

PGC 21634
Not an NGC object but listed here because sometimes misidentified as
NGC 2433
A 15th-magnitude spiral galaxy (type Sab?) in Canis Minor (RA 07 42 56.9, Dec +09 20 53)
Based on a recessional velocity of 18760 km/sec (per LEDA), a straightforward calculation indicates that PGC 21634 is about 875 million light years away. However, for such distant objects, the expansion of the Universe during the time their light took to reach us must be taken into account. Doing that indicates that PGC 21634 was about 810 million light years away when the light by which we see it was emitted, about 835 million years ago (the difference between the two numbers being due to the expansion of the intervening space during the light's journey). Given that and its apparent size of 0.5 by 0.5 arcmin, PGC 21634 is about 110 thousand light years across. Note: NED lists the galaxy as a member of Abell 592.
SDSS image of spiral galaxy PGC 21634
Above, a 2.4 arcmin wide closeup of PGC 21634 (which is not NGC 2433)
Below, a 12 arcmin wide region centered on the galaxy; also shown at lower right is the correct NGC 2433
SDSS image of region near PGC 21634, overlaid with a DSS image of the (lower left) portion of the field not covered by the SDSS database

NGC 2434 (= PGC 21325)
Discovered (Dec 23, 1834) by
John Herschel
An 11th-magnitude elliptical galaxy (type E1?) in Volans (RA 07 34 51.5, Dec -69 17 04)
Per Dreyer, NGC 2434 (= John Herschel's GC 1561, 1860 RA 07 35 10, NPD 158 58.1) is "pretty bright, small, round, pretty much brighter middle, three 11th-magnitude stars to north". The position precesses to RA 07 34 51.2, Dec -69 16 57, almost dead center on the galaxy, and there are three stars just to the north, so the identification is certain. Based on a recessional velocity of 1390 km/sec, NGC 2434 is about 65 million light years away, in good agreement with redshift-independent distance estimates of 55 to 80 million light years. Given that and its apparent size of 2.5 by 2.3 arcmin, it is about 45 thousand light years across.
DSS image of elliptical galaxy NGC 2434
Above, a 3 arcmin wide closeup of NGC 2434
Below, a 12 arcmin wide region centered on the galaxy
DSS image of region near elliptical galaxy NGC 2434

NGC 2435 (= PGC 21676)
Discovered (Oct 26, 1786) by
William Herschel
A 13th-magnitude spiral galaxy (type Sa?) in Gemini (RA 07 44 13.4, Dec +31 39 02)
Per Dreyer, NGC 2435 (= John Herschel's GC 1562, 1860 RA 07 35 18, NPD 58 01.2) is "faint, small, slightly brighter middle". The position precesses to RA 07 44 13.5, Dec +31 39 04, dead center on the galaxy, so the identification is certain. Based on a recessional velocity of 4190 km/sec, NGC 2435 is about 195 million light years away, in fair agreement with redshift-independent distance estimates of 150 to 170 million light years. Taking an "average" distance of about 180 million light years, its apparent size of 2.1 by 0.5 arcmin suggests that it is about 110 thousand light years across.
SDSS image of spiral galaxy NGC 2435
Above, a 2.4 arcmin wide closeup of NGC 2435
Below, a 12 arcmin wide region centered on the galaxy
SDSS image of region near spiral galaxy NGC 2435

NGC 2436 (probably =
NGC 2431 = PGC 21711)
Discovered (Mar 17, 1790) by William Herschel (and later listed as NGC 2431)
Discovered (Feb 16, 1831) by John Herschel (and later listed as NGC 2436)
A 13th-magnitude spiral galaxy (type SBa?) in Lynx (RA 07 45 13.3, Dec +53 04 32)
Per Dreyer, NGC 2436 (= John Herschel's GC 1563, 1860 RA 07 35 19, NPD 37 35.9) is "very faint, very small, round, brighter middle". The position precesses to RA 07 46 07.8, Dec +52 04 12, an almost completely empty area of the sky that contains nothing resembling its description, so there is obviously something wrong with the younger Herschel's position. Per Corwin the probable explanation, based on the essentially identical description of NGC 2431 by William Herschel and NGC 2436 by his son, is that they might have observed the same object, and John simply recorded the Right Ascension 1 minute of time too large, and the North Polar Distance 1 degree too large. Such blunders are common in hand-reductions of positional measurements, and if that is what happened then the 1860 position should have been RA 07 34 19, NPD 36 35.9, and the 2000.0 position would be RA 07 45 16.3, Dec +53 04 22, which is only 0.7 arcmin southwest of the center of NGC 2431. Of course one can never be certain whether such explanations are correct, but in a case like this, where the descriptions match so well and the errors are so "simple", the tentative identity of the two NGC listings seems nearly certain. Given that, see NGC 2431 for a discussion and images of the object. (Note: A Wikisky search for NGC 2436 shows NGC 2431, demonstrating the essentially universal acceptance of this argument.)

NGC 2437 (=
M46 = OCL 601)
Discovered (Feb 19, 1771) by Charles Messier
A 6th-magnitude open cluster (type III2m) in Puppis (RA 07 41 46.8, Dec -14 48 36)
Per Dreyer, NGC 2437 (= Messier 46, 1860 RA 07 35 24, NPD 104 29.8) is "a remarkable object, cluster, very bright, very rich, very large, involving a planetary nebula". The position precesses to RA 07 41 49.8, Dec -14 49 19, about 1 arcmin southeast of the center of the cluster, but between the difficulty of determining the center of such an object and the presence of the planetary nebula (NGC 2438) the identification is certain. M46 consists of several hundred stars scattered across a region nearly half a degree across, about 5500 light years away. Given its distance and apparent size, the cluster is about 50 light years across. Based on the turnoff point of its Hertzsprung-Russell Diagram, it is thought to have formed about 300 million years ago. As noted above there is a planetary nebula (NGC 2438) located near the northeastern edge of the cluster, but it does not have the same radial velocity as cluster members, and is almost certainly a foreground object (probably only about 3000 light years away) which just happens to be in the same direction.
Misti Mountain Observatory image of open cluster NGC 2437, also known as M46, superimposed on an NOAO background; also shown is planetary nebula NGC 2438
Above: A 28 arcmin wide composite of M46 (a Misti Mountain Observatory image superimposed on a wider NOAO view), also showing NGC 2438. (Background Image Credits: N.A.Sharp/AURA/NSF/NOAO; Foreground Image Credits and © Jim Misti, Misti Mountain Observatory; used by permission.) Also see NGC 2422 for a wide-field image showing several clusters in the region

NGC 2438
Discovered (Mar 19, 1786) by
William Herschel
An 11th-magnitude planetary nebula in Puppis (RA 07 41 50.6, Dec -14 44 05)
Per Dreyer, NGC 2438 (= John Herschel's GC 1565, 1860 RA 07 35 26, NPD 104 25.0) is a "planetary nebula, pretty bright, pretty small, very slightly extended, mottled but not resolved, 3.75 sec of time diameter". The position precesses to RA 07 41 52.0, Dec -14 44 31, about 0.5 arcmin southeast of the center of the planetary, but well within its border; and for such a unique feature, even if the measurement lay outside its boundary there would be no doubt of the identification. The actual size of the planetary is 1.1 by 1.1 arcmin, slightly larger than the size stated by Dreyer. The central star is an 18th-magnitude white dwarf. As noted for M46, the planetary nebula does not have the same radial velocity as the cluster members. Their radial velocities are all within about 4 km/sec of the same value, while the planetary nebula's radial velocity differs from the average by 30 km/sec; so it is not connected with the cluster, but is instead a foreground object (probably only about 3000 light years away). Very long exposures show that the nebula has an extended halo, presumably from the expansion and dispersion of an early phase of its formation, while the more easily visible portion probably dates to the death of the red giant which collapsed to form the white dwarf in its center. Given the estimated distance of the nebula and its apparent size, the easily visible portion is about 1 light year (approximately 60 thousand AUs) in diameter.
Misti Mountain Observatory image of planetary nebula NGC 2438
Above, a 2.4 arcmin wide closeup of NGC 2438
(Image Credit and Copyright above and below: Jim Misti, Misti Mountain Observatory; used by permission)
Below, a 12 arcmin wide region centered on the planetary nebula; for a wider view, see NGC 2437
Composite of Misti Mountain Observatory image and DSS image of that region near planetary nebula NGC 2438 not covered by the Misti Mountain image


NGC 2439 (= OCL 688)
Discovered (Jan 28, 1835) by
John Herschel
A 7th-magnitude open cluster (type II3m) in Puppis (RA 07 40 45.4, Dec -31 41 33)
Per Dreyer, NGC 2439 (= John Herschel's GC 1566, 1860 RA 07 35 26, NPD 121 19.8) is a "cluster, bright, pretty rich, pretty large, slightly compressed, stars of 9th and 12th through 14th magnitude". The position precesses to RA 07 40 52.0, Dec -31 39 14, almost 3 arcmin to the north of the cluster, but still well within its outline, and close to one of its brightest members; so the identification is certain. A fairly recent study of the cluster indicates that it has over 100 members scattered across a 10 arcmin wide region about 13500 light years away. Given the supposed distance and apparent size, the cluster is about 40 light years across. The earliest main sequence star is of type B5, suggesting a relatively young age of about 20 million years.
DSS image of open cluster NGC 2439
Above, a 12 arcmin wide region centered on NGC 2439

NGC 2440
Discovered (Mar 4, 1790) by
William Herschel
A 9th-magnitude planetary nebula in Puppis (RA 07 41 55.4, Dec -18 12 29)
Per Dreyer, NGC 2440 (= John Herschel's GC 1567, 1860 RA 07 35 40, NPD 107 53.0) is "planetary nebula, considerably bright, not very well defined". The position precesses to RA 07 41 54.8, NPD -18 12 33, within 0.2 arcmin of the center of the nebula, so the identification is certain. NGC 2440 lies about 4000 light-years from the Sun, and given its size (about 74 by 42 arc-seconds), is nearly 100 thousand AUs (approximately 1 1/2 light years) across its longest dimension, with a central star of 14th magnitude. The planetary nebula must be relatively young, as its white dwarf is one of the hottest known (more than 200 thousand Kelvins, or about 400 thousand Fahrenheit degrees), and despite its small size (about 1/40 the size of the Sun, or 2 to 3 Earth diameters), is about 250 times brighter than our Sun. The complex structure of the nebula (shown in more detail in the second image) indicates several episodes of mass ejection, in different directions. Both HST images are "false-color" images, meant to bring out detail which would not be visible in the essentially monochrome view that the human eye would perceive (even if close to the nebula), but the first is meant to approximate "natural" colors, while the second makes no effort to do so.
HST image of planetary nebula NGC 2440 in simulated natural color
Above, a simulated natural color image of the core of the planetary nebula
(Image Credits: H. Bond (STScI), R. Ciardullo (PSU), WFPC2, HST, (processing by Forrest Hamilton), NASA
Below, a false-color image of the entire nebula
(Image Credits: (NASA, ESA, K. Noll (STScI) Acknowledgment: Hubble Heritage Team (STScI / AURA), HubbleSite
HST image of planetary nebula NGC 2440 showing the entire structure of the nebula
Below, a 12 arcmin wide region centered on the planetary nebula
(Image Credits: Partial superposition of Jeff Cremer/Adam Block/NOAO/AURA/NSF/AOP image on DSS image
Composite of NOAO and DSS images of region near planetary nebula NGC 2440

NGC 2441 (= PGC 22031)
Discovered (Aug 8, 1882) by
Wilhelm Tempel
A 12th-magnitude spiral galaxy (type SAB(r)b) in Camelopardalis (RA 07 51 54.5, Dec +73 00 55)
Per Dreyer, NGC 2441 (= Tempel's list VI (#1), 1860 RA 07 36 26, NPD 16 40.7) is "very faint, pretty small". The position precesses to RA 07 52 50.7, Dec +72 58 41, about 5 arcmin southeast of the galaxy identified as NGC 2441; but there is nothing else nearby, and no one has expressed any concern about the identification, so it is presumably reasonably certain. Based on a recessional velocity of 3470 km/sec, NGC 2441 is about 160 million light years away, in better agreement with redshift-independent distance estimates of 125 to 400 million light years than they are with each other. Given that and its apparent size of 2.0 by 1.7 arcmin, it is about 100 thousand light years across.
DSS image of spiral galaxy NGC 2441
Above, a 2.4 arcmin wide closeup of NGC 2441
Below, a 15 arcmin wide region centered on the galaxy; Tempel's position is shown by the box at left
DSS image of region near spiral galaxy NGC 2441

NGC 2442 and NGC 2443 (= PGC 21373)
Discovered (Dec 23, 1834) by
John Herschel (and later listed as NGC 2442)
Discovered (Dec 23, 1834) by John Herschel (and later listed as NGC 2443)
A 10th-magnitude spiral galaxy (type SAB(s)bc pec) in Volans (RA 07 36 23.8, Dec -69 31 51)
Per Dreyer, NGC 2442 (= John Herschel's GC 1568, 1860 RA 07 36 44, NPD 159 12.8) is "considerably large, very faint, round", and NGC 2443 (= John Herschel's GC 1569, same coordinates) is "pretty large, very faint, round", and the pair are a "double nebula, 40° position angle, double star involved with middle". The position precesses to RA 07 36 20.6, Dec -69 31 56, about 0.8 arcmin west of the center of the galaxy, but well within its very large outline; so the identification is certain. Per Corwin, the reason for the double listing is that on Herschel's first sweep of the area, he observed the southwestern and northeastern parts of the galaxy as two faint nebulae separated by what appeared to be a stellar middle (which part being which is determined by the position angle, which indicates that the second object is to the northeast of the first); and although three subsequent observations stated that the two objects were actually a single large nebula, Dreyer's entry maintained the original double listing. Based on a recessional velocity of 1465 km/sec, NGC 2442/43 is about 68 million light years away, in reasonable agreement with a redshift-independent distance estimate of 56 million light years. Given that and its apparent size of 5.5 by 4.9 arcmin, it is about 110 thousand light years across. Used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type SAB(s)bc pec.
DSS image of the spiral galaxy listed as NGC 2442 and 2443
Above, a 7 arcmin wide closeup of NGC 2442/43
Below, the same image labeled per the original NGC
Labeled DSS image of the spiral galaxy listed as NGC 2442 and 2443
Below, a deep-sky image of the galaxy, with North at upper left (Image Credits: ESO)
ESO image of the spiral galaxy listed as NGC 2242 and 2443
Below, a 12 arcmin wide region centered on the galaxy, with North at the top
ESO image of region near the spiral galaxy listed as NGC 2242 and 2243 overlaid on a DSS image of regions not covered by the ESO image

NGC 2444 (= PGC 21774, and with
NGC 2445 = Arp 143)
Discovered (Jan 18, 1877) by Édouard Stephan
A 13th-magnitude lenticular galaxy (type S0 pec) in Lynx (RA 07 46 53.0, Dec +39 01 57)
Per Dreyer, NGC 2444 (= Stephan's list VIII (#22), 1860 RA 07 37 26, NPD 50 37.9) is "very faint, much brighter middle". The position precesses to RA 07 46 53.9, Dec +39 01 56, about 0.2 arcmin east of the center of the galaxy, but well within its outline, so the identification is certain. Based on a recessional velocity of 4050 km/sec, NGC 2444 is about 188 million light years away. Given that and its apparent size of 1.2 by 0.8 arcmin, it is about 65 thousand light years across. The galaxy is interacting with NGC 2445, hence their designation as Arp 143. Given the apparent magnitude of that interaction, the pair may be within a hundred thousand light years of each other. Theoretical studies indicate that the two galaxies recently collided and may be about to undergo a second collision, which should eventually result in their merger into a single galaxy. Despite the close interaction (or even collision), NGC 2444's larger mass (about twice that of NGC 2445) has caused it to be much less distorted by their interaction.
SDSS image of lenticular galaxy NGC 2444 and peculiar galaxy NGC 2445, collectively known as Arp 143
Above, a 3.2 arcmin wide closeup of NGC 2444 and 2445
Below, a 12 arcmin wide region centered on the pair
SDSS image of region near lenticular galaxy NGC 2444 and peculiar galaxy NGC 2445, collectively known as Arp 143

NGC 2445 (= PGC 21776, and with
NGC 2444 = Arp 143)
Discovered (Jan 18, 1877) by Édouard Stephan
A 13th-magnitude peculiar galaxy (type pec?) in Lynx (RA 07 46 55.0, Dec +39 00 56)
Per Dreyer, NGC 2445 (= Stephan's list VIII (#23), 1860 RA 07 37 28, NPD 50 38.9) is "very faint, much brighter middle, small star attached to south". The position precesses to RA 07 46 55.8, Dec +39 00 55, about 0.2 arcmin east of the center of the galaxy and well within its outline, so the identification is certain. Based on a recessional velocity of 4000 km/sec, NGC 2445 is about 186 million light years away. Given that and its apparent size of 1.4 by 1.1 arcmin, it is about 75 thousand light years across. The galaxy is interacting with NGC 2444 (which see for images), hence their designation as Arp 143. Given the apparent magnitude of that interaction, the pair may be within a hundred thousand light years of each other. Theoretical studies indicate that the two galaxies recently collided and may be about to undergo a second collision, which should eventually result in their merger into a single galaxy. Because of its smaller mass (about half that of NGC 2444), NGC 2445 has been more distorted by their interaction. Used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type Pec.

PGC 200237
Listed here because of its apparent association with
NGC 2445
A 15th-(B)magnitude galaxy (type ?) in Lynx (RA 07 46 55.6, Dec +39 00 26)
PGC 200237 appears to be a compact galaxy lying between us and NGC 2445 (available images show no interaction between them, but their quality leaves much to be desired, so a closer relationship is possible). Its apparent size is less than 0.1 arcmin; nothing else seems to be available. For images of it and NGC 2445, see NGC 2444.

NGC 2446 (= PGC 21860)
Discovered (Feb 10, 1831) by
John Herschel
A 13th-magnitude spiral galaxy (type Sb?) in Lynx (RA 07 48 39.2, Dec +54 36 42)
Per Dreyer, NGC 2446 (= John Herschel's GC 1570, 1860 RA 07 37 36, NPD 35 03.4) is "faint, among 4 stars". The position precesses to RA 07 48 44.8, Dec +54 36 27, about 0.3 arcmin southeast of the center of the galaxy and well within its outline, so the identification is certain. Based on a recessional velocity of 5670 km/sec, NGC 2446 is about 265 million light years away, in reasonable agreement with redshift-independent distance estimates of 210 to 255 million light years. Given that and its apparent size of 1.9 by 1.0 arcmin, it is about 150 thousand light years across.
DSS image of spiral galaxy NGC 2446
Above, a 2.4 arcmin wide closeup of NGC 2446
Below, a 12 arcmin wide region centered on the galaxy
DSS image of region near spiral galaxy NGC 2446

NGC 2447 (=
M93 = OCL 649)
Discovered (Mar 20, 1781) by Charles Messier
A 6th-magnitude open cluster (type IV1p) in Puppis (RA 07 44 30.0, Dec -23 51 24)
Per Dreyer, NGC 2447 (= Messier 93, 1860 RA 07 38 39, NPD 113 32.7) is a "cluster, large, pretty rich, slightly compressed, stars from 8th to 13th magnitude". The position precesses to RA 07 44 35.0, Dec -23 52 46, almost 1.5 arcmin south of the putative center of the cluster, but well within its impressive structure, so the identification is certain. M93 is an open cluster which contains nearly a hundred fairly bright stars scattered across a region about 22 arcmin in diameter, around 3600 light years away. Given that, it must be about 20 to 25 light years in diameter. The brightest Main Sequence stars in the cluster are of spectral type B9, suggesting that the cluster is about 100 million years old. As shown in the image below, there is a strong concentration of stars near its center, and a sparser scattering to the east.
DSS image of open cluster NGC 2447, also known as M93
Above, a 24 arcmin wide region centered on M93

NGC 2448
Discovered (Jan 7, 1831) by
John Herschel
A stellar grouping in Puppis (RA 07 44 34.5, Dec -24 40 51)
Per Dreyer, NGC 2448 (= John Herschel's GC 1572, 1860 RA 07 38 41, NPD 114 21.2) is a "cluster of 18 or 20 stars from 11th to 13th magnitude". The position precesses to RA 07 44 34.1, Dec -24 41 16, about 0.4 arcmin south of the putative center of the cluster, but both positions are within the glare of 6th magnitude HD 62747, which is generally taken as the center of the cluster, so the identification is certain. Most observers agree with Dreyer that the "cluster" appears to consist of 18 to 20 stars of 11th to 13th magnitude, scattered across a region about 5 arcmin in diameter. However, it is generally felt that this is not a true cluster, but merely a minor accidental grouping of stars in a region already filled with them, and in the image below stars seem to be randomly scattered across the entire region, without any sign of a particular grouping; so whatever the nature of NGC 2448, it is neither an obvious nor significant object.
DSS image of stellar grouping NGC 2448
Above, a 15 arcmin wide region centered on NGC 2448

NGC 2449 (= PGC 21802)
Discovered (Jan 18, 1874) by
Édouard Stephan
A 13th-magnitude spiral galaxy (type Sab?) in Gemini (RA 07 47 20.4, Dec +26 55 50)
Per Dreyer, NGC 2449 (= Stephan's list VI (#9), 1860 RA 07 38 45, NPD 62 43.8) is "extremely faint, extremely small, round, brighter middle, mottled but not resolved". The position precesses to RA 07 47 21.5, Dec +26 55 52, about 0.3 arcmin east of the center of the galaxy but within its outline, so the identification is certain. Based on a recessional velocity of 4890 km/sec, NGC 2449 is about 225 million light years away. Given that and its apparent size of 1.3 by 0.6 arcmin, it is about 85 thousand light years across.
SDSS image of spiral galaxy NGC 2449, also showing part of spiral galaxy IC 476
Above, a 2.4 arcmin wide closeup of NGC 2449 and part of IC 476
Below, a 12 arcmin wide region centered on the galaxy; also shown are NGC 2450, and IC 476 and 2205
SDSS image of region near spiral galaxy NGC 2449, also showing spiral galaxies NGC 2450, IC 476 and IC 2205
Celestial Atlas
(NGC 2350 - 2399) ←     NGC Objects: NGC 2400 - 2449     → (NGC 2450 - 2499)