Based on recessional velocity of 4805 km/sec, about 210 million light years away. Given that and apparent size of 0.8 by 0.15 arcmins, about 50 thousand light years in diameter.

(See a discussion of Hodierna for an explanation of why he received no credit for any of his NGC discoveries; in this case, there is the additional problem that he did not include the object in his short catalog of discoveries. Instead, he drew a picture (V.3) of a region in Puppis which is probably of this cluster, but lacking catalog information, is not as certainly identified.) As it happens, the "cluster" is actually two clusters, which just happen to be in exactly the same direction, nearly centered on the brightest star in the group, the 3.6 magnitude yellow giant, c Puppis. The nearer cluster, NGC 2451A, is about 620 light years away, while the more distant NGC 2451B is about 1170 light years away. Each seems to contain a hundred or more stars (70 have been Main Sequence stars have been confirmed in NGC 2451A, just counting down to magnitude 15), and to have formed at about the same time, 50 to 60 million years ago; so the two may have formed in the same star-forming region, at about the same time, and gradually drifted apart since their formation. The overall apparent size of the "cluster" is about 45 arcmin, which implies that the nearer cluster (which should look larger, given its smaller distance) is about 8 light years across, and although information about the more distant one is harder to come by, it is probably also less than 10 light years in diameter.

The first IC states (per Burnham) "Not planetary, but bi-nuclear" (apparently, incorrectly). The images below are badly overexposed, but no better images seem to be available for this object.

About two dozen stars thickly clustered within a 3 arcmin wide region. Planetary nebula NGC 2452 is only 8 arcmin to the south-southwest, so the wider-field image is set up to show its position, as well.

Per Dreyer, NGC 2455 (= John Herschel's GC 1576, 1860 RA 07 42 52, NPD 110 57.1) is "cluster, considerably large, pretty rich, slightly compressed, 12th-magnitude stars". The position precesses to RA 07 48 57.5, Dec -21 17 57, which is so close to wherever the "center" of the cluster lies that I've adopted it as the official position for this entry. NGC 2455 consists of several dozen stars of about 12th magnitude scattered across a 10 to 15 arcmin wide region, but the surrounding star field is so dense that it's hard to tell where the "cluster" ends and the starry background begins.

Per Dreyer, NGC 2458 (= 3rd Lord Rosse, Bigourdan, 1860 RA 07 44 04, NPD 32 56.0) is "very faint, 12th magnitude star close". (Although Dreyer credits the report of the discovery to William Parsons, 3rd Earl of Rosse, he notes that many of Rosse's nebular discoveries were actually made by his assistants, George Stoney, Bindon Stoney, and R. J. Mitchell.) This is one of eight NGC objects for which the history of observation is complex, and identifications and positions are not always as certain or satisfactory as might be hoped. Per Corwin, the Herschels observed NGC 2463 and 2469. Lord Rosse and his assistants also observed those galaxies, but noted the presence of ten (meaning eight additional) objects in an east-west line, without bothering to measure any of their positions. Despite the lack of any direct evidence for the existence or location of the objects, Dreyer (who worked for the 4th Lord Rosse) dutifully added NGC numbers for each of the eight additional "objects" (namely, NGC 2458, 2461, 2462, 2464, 2465, 2471, 2472 and 2473). Later, Bigourdan made a series of observations which seemed to confirm the existence and position of the first six of those objects (hence Dreyer's credit for the 3rd Lord Rosse and Bigourdan). For the last two, NGC 2472 and 2473, he never made any observations; so the identifications of those objects are very uncertain; but as can be seen at the entry for each of the eight "additions", there are problems with the identification of almost every one. For NGC 2458, Bigourdan's position precesses to RA 07 55 28.8, Dec +56 42 27, about 22.8sW and 12"S of the correct position, so THIS ENTRY NEEDS A LOT OF WORK BEFORE FINALIZING.

Per Dreyer, NGC 2459 (= John Herschel's GC 1578, 1860 RA 07 44 24, NPD 80 05.5) is "very faint, small, partially resolved group (some stars seen) plus nebulosity". A note at the end of the NGC adds (per John Herschel) that several efforts to see any nebulosity were unsuccessful, and the first IC adds "No nebulosity, only a couple of faint stars seen by Spitaler)", so the object is just a group of faint stars. The position precesses to RA 07 52 02.8, Dec +09 33 13, about 0.2 arcmin southwest of the center of an asterism of five 13th and 14th magnitude stars, close enough that there is no real doubt about the identification with that group. The main question is whether any other stars should be included in the NGC object. Most of the faint scattering of stars surrounding the five central stars are not visible with telescopes comparable to Herschel's, and most observers agree that NGC 2459 consists of only the approximately 1 arcmin wide asterism.

Several arms extend for long distances from the central galaxy, perhaps as a result of an interaction with PGC 213434; but since the distance of that galaxy is unknown, the apparent interaction may be illusory.

Per Dreyer, NGC 2461 (= 3rd Lord Rosse, Bigourdan, 1860 RA 07 45 23, NPD 32 58.2) is "13th magnitude star, slightly nebulous". (Although Dreyer credits the report of the discovery to William Parsons, 3rd Earl of Rosse, he notes that many of Rosse's nebular discoveries were actually made by his assistants, George Stoney, Bindon Stoney, and R. J. Mitchell.) This is one of eight NGC objects for which the history of observation is complex, and identifications and positions are not always as certain or satisfactory as might be hoped. Per Corwin, the Herschels observed NGC 2463 and 2469. Lord Rosse and his assistants also observed those galaxies, but noted the presence of ten (meaning eight additional) objects in an east-west line, without bothering to measure any of their positions. Despite the lack of any direct evidence for the existence or location of the objects, Dreyer (who worked for the 4th Lord Rosse) dutifully added NGC numbers for each of the eight additional "objects" (namely, NGC 2458, 2461, 2462, 2464, 2465, 2471, 2472 and 2473). Later, Bigourdan made a series of observations which seemed to confirm the existence and position of the first six of those objects (hence Dreyer's credit for the 3rd Lord Rosse and Bigourdan). For the last two, NGC 2472 and 2473, he never made any observations; so the identifications of those objects are very uncertain; but as can be seen at the entry for each of the eight "additions", there are problems with the identification of almost every one. For NGC 2461, Bigourdan's position precesses to RA 07 56 46.7, Dec +56 40 00. There is nothing at that location, so THIS ENTRY NEEDS A LOT OF WORK BEFORE FINALIZING. LEDA incorrectly identifies NGC 2461 as the galaxy PGC 22220; and perhaps for that reason, so does Wikisky; but given the confusion about the identification of the NGC object, such "errors" are to be expected.

Per Dreyer, NGC 2462 (= 3rd Lord Rosse, Bigourdan, 1860 RA 07 45 29, NPD 32 58.0) is "very faint, very small, very slightly brighter middle". (Although Dreyer credits the report of the discovery to William Parsons, 3rd Earl of Rosse, he notes that many of Rosse's nebular discoveries were actually made by his assistants, George Stoney, Bindon Stoney, and R. J. Mitchell.) This is one of eight NGC objects for which the history of observation is complex, and identifications and positions are not always as certain or satisfactory as might be hoped. Per Corwin, the Herschels observed NGC 2463 and 2469. Lord Rosse and his assistants also observed those galaxies, but noted the presence of ten (meaning eight additional) objects in an east-west line, without bothering to measure any of their positions. Despite the lack of any direct evidence for the existence or location of the objects, Dreyer (who worked for the 4th Lord Rosse) dutifully added NGC numbers for each of the eight additional "objects" (namely, NGC 2458, 2461, 2462, 2464, 2465, 2471, 2472 and 2473). Later, Bigourdan made a series of observations which seemed to confirm the existence and position of the first six of those objects (hence Dreyer's credit for the 3rd Lord Rosse and Bigourdan). For the last two, NGC 2472 and 2473, he never made any observations; so the identifications of those objects are very uncertain; but as can be seen at the entry for each of the eight "additions", there are problems with the identification of almost every one. For NGC 2462, Bigourdan's position precesses to RA 07 56 52.7, Dec +56 40 11, about 21.8sE, 1'1" S of the "correct" position, so THIS ENTRY NEEDS A LOT OF WORK BEFORE FINALIZING.

(Note: See the discussion of Hodierna for an explanation of why he was not credited with the discovery of any NGC object.) 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, that corresponds to a physical diameter of about 15 light years. (See NGC 2422 for an image of the cluster, and a discussion of its complicated history of discovery.)