Note: A Wikisky search for NGC 2603 incorrectly shows NGC 2606 (which is also incorrectly labeled as NGC 2603); so use its coordinates to view it. This is apparently due to PGC 24117 being incorrectly listed as both NGC 2603 and 2606 in some catalogs.

Note: A Wikisky search for NGC 2605 shows the correct object, but does not indicate its NGC identity.

Note: A Wikisky search for NGC 2606 shows the correct galaxy, but labels it as NGC 2603. This is apparently due to PGC 24117 being incorrectly listed as both NGC 2603 and 2606 in some catalogs.

Based on a recessional velocity of 3530 km/sec, NGC 2607 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.

Based on a recessional velocity of 2135 km/sec, NGC 2608 is about 100 million light years away, in good agreement with redshift-independent distance estimates of 70 to 100 million light years. Given that and its apparent size of 2.3 by 1.4 arcmin, it is about 65 thousand light years across.

Per Dreyer, NGC 2609 (= John Herschel's GC 1671, 1860 RA 08 26 49, NPD 150 38.5) is "cluster, pretty small, slightly rich, slightly compressed". Of two observations by Herschel, the more detailed says "a double star, chief of a cluster 8th class of scattered stars, 6 arcmin diameter, not very rich or compressed". The position precesses to RA 08 29 31.2, Dec -61 06 41, within 0.4 arcmin of the double star in question, so the identity is certain. Despite this, some catalogs incorrectly list the object as "Not Found" or "nonexistent"; perhaps for that reason, a Wikisky search for NGC 2609 shows the correct region, but does not indicate that it is an NGC object.

The second IC says "Howe is wrong in placing this 1 degree north (wrong star). d'Arrest and Schonfeld agree with h." (that is, with John Herschel's GC entry). Note: Wikisky images of NGC 2610 grossly overexpose the nebula; so an original (monochrome) DSS image has been overlaid on the Wikisky images to produce the views below.

The second IC says (per Howe) "not bright but faint".

Note: A Wikisky search for NGC 2617 incorrectly labels a galaxy to the east of it, PGC 24136, as NGC 2617 (perhaps because Steinicke's NGC/IC database, although giving the correct coordinates for NGC 2617, incorrectly lists it as PGC 24136?).

The first IC lists a corrected RA (per Bigourdan) of 08 29 01

Based on a recessional velocity of 8580 km/sec, NGC 2622 is about 400 million light years away. Given that and its apparent size of 0.95 by 0.65 arcmin, it is about 110 thousand light years across. The galaxy is notable for its gravitational interaction with the nearby galaxy, PGC 24266. Both galaxies have extended arms of gas, stars and clusters of stars strewn into space by their interaction. One result of their interaction is a starburst in the core of NGC 2622, causing it to be classified as a Seyfert galaxy (type Sy1.8). The other galaxies in the field of view do not appear to be taking part in the gravitational interactions, and are probably foreground or background objects; but by and large, nothing is known about them anyway.

Based on a recessional velocity of 8470 km/sec, PGC 24266 is about 395 million light years away. It is notable for its obvious gravitational interaction with NGC 2622 (which see for images of the pair), which implies that the two galaxies are even closer than indicated by their recessional velocities -- probably no more than a couple of hundred thousand light years from each other. Given their common distance and the galaxy's apparent size of 0.4 by 0.3 arcmin, it is about 45 thousand light years across; but that does not take into account the long tail of gas and stars streaming away to its southwest.

Two galaxies recently collided and merged to form this galaxy, which is in the late stages of its merger, having developed a nearly common (though very distorted and spectacularly bright) core, but still shows the aftereffects of its merger in two spectacularly long arms of stars, star clusters and gases thrown out into intergalactic space and now filled with hot, bright young clusters of stars which heat and light up the gases surrounding them. Based on its recessional velocity of 5550 km/sec, NGC 2623 is about 260 million light years away, in reasonable agreement with redshift-independent distance estimates of 250 to 350 million light years. Given that and its apparent size of 2.4 by 0.7 arcmin, it is about 180 thousand light years across. The core of the galaxy, filled with exceptionally large numbers of bright young stars, causes it to be classified as a Seyfert galaxy (type Sy2).

Praesepe, or the Beehive Cluster, is easily visible as a "little cloud" of stars in dark skies, and was already known in ancient times, when dark night skies were common. The first known mention of its existence is by Aratos, as part of a poem meant to reproduce the (now lost) prose of Eudoxus of Cnidus. Eudoxus was the first to propose a system of turning spheres as an explanation of the motions of heavenly bodies, and apparently as part of that work he discussed the rising and setting of various constellations. A review of Aratos' work by Hipparchus shows that Eudoxus' work was still extant at the time of Hipparchus, who pointed out errors in both the original prose and (more critically) its poetic transformation. Although practically all of Hipparchus' astronomical works have been lost, we know through Ptolemy that Hipparchus made thousands of relatively accurate observations of celestial objects, and on that basis can be confidently assigned the place of honor as the first person to estimate a reasonably accurate position for the cluster; but the existence of the "little cloud" must have been known no later than the time of Eudoxus and more likely, at least as early as the time of Eudoxus' father, Aeschines of Cnidus, who was an avid observer of the skies. The cluster was first resolved into stars by Galileo, and not long after, by some of his contemporaries (for instance, Hodierna had it as #1 in his list of objects which were nebulous to the naked eye, but resolved into stars by a telescope); so it had a long history before Messier added it to his catalog. Per Dreyer, NGC 2632 (= Hipparchus, Messier 44, 1860 RA 08 32, NPD 69 32) is "Praesepe Cancri". The position precesses to RA 08 40 03.8, Dec +19 58 33, well within the 95 arcmin diameter of the cluster; so even without the millennia of historical precedence, the identification would be certain. Praesepe is one of the nearest clusters to the Sun, being only about 575 light years away. Given its distance and apparent size, it is about 15 light years across. Studies of the proper motion of objects in the region of the cluster show that about 200 stars share the same motion, and must be cluster members. The nature of the brightest stars in the cluster suggests an age of 730 million years, which is not much less than the 790 million years estimated for the Hyades, and both clusters have similar proper motions, so it is possible that they originated in the same (unknown) star-forming region, at about the same time.