Apparent size 10 arcmin

Apparent size 10 arcmin

Apparent size 18 arcmin, on the northeastern side of the Rosette Nebula

Historical Identification: Per Dreyer, NGC 2253 (= GC 1431 = WH VII 54, 1860 RA 06 27 56, NPD 24 02.3) is "very faint, stars extremely small (faint)". (Herschel himself described the object as "A very faint patch or small cluster of extremely small (faint) stars", hence his placing it in his class VII, which corresponds to compressed clusters). The position precesses to RA 06 41 59.7, Dec +65 50 35, but there is nothing there, nor anywhere near there. PGC 19501 was formerly misidentified (and is still misidentified in some places) as NGC 2253, so it is discussed in the following entry.
Analysis Of Possible Candidates (1): Herschel stated that his VII 54 was 29 minutes 1 second east and 16 arcmin north of 36 Camelopardalis; but if the 16 arcmin is a typographical error and was actually 46 arcmin (a half degree error of a sort not all that uncommon in Herschel's measurements), then (converting the J2000 position of 36 Cam to the 1788 equinox of observation, adding Herschel's offsets to obtain the 1788 position of his VII 54 and then precessing the result to J2000 coordinates), we would obtain a position of RA 06 42 09.5, Dec +66 20 36, which lies on the western rim of the apparent cluster of stars listed above (per Corwin, first suggested to be NGC 2253 by Alister Ling, and verified as looking like Herschel's description of his VII 54 by Bob Jardine). Obviously, this identification cannot be certain, but it is at least reasonable, and seems the most likely of various candidates.
Analysis Of Possible Candidates (2): (Steve Gottlieb's observation) Physical Information: If the group of stars listed above, about 6 by 12 arcmin apparent size.

Historical Identification: The first (mis)identification of PGC 19501 as NGC 2253 appears to have been in the 1973 RNGC. That catalog, which was very quickly done, generally chose the closest galactic object to an NGC position without consideration of whether it was a reasonable candidate or not. In this case it was definitely not reasonable, as even if Herschel had observed it, it could not have matched his description of what he did observe, and though he is known to have made a number of single digit errors in one position or another, the large errors in both right ascension and declination between his position and that of PGC 19501 would be unprecedented.
Physical Information: To be added ASAP

Apparent size 6 arcmin

Apparent size 1.5 by 0.7 arcmin

Apparent size 2.3 by 2.0 arcmin

Historical Identification: Per Dreyer, NGC 2257 (= GC 1434 = JH 3057, 1860 RA 06 29 26, NPD 154 13.4) is "faint, considerably large, round, very gradually a little brighter middle, mottled but not resolved, 17.0 seconds of time diameter". The position precesses to RA 06 30 11.2, Dec -64 19 28, right on the cluster listed above, the description fits and there is nothing comparable nearby, so the identification is certain.
Physical Information: NGC 2257 is a globular cluster on the outskirts of the Large Magellanic Cloud. It is one of the oldest clusters in the LMC, with an age of about 12 billion years (most of the details herein per Jeon et al, ApJ 147, 2014). The LMC is about 160 to 165 thousand light years away (given the galaxy's physical size, some parts of it are closer than that, and others further away). Given that and the cluster's apparent size of about 3.5 arcmin (from the images below), it is about 17 light years across, but the best fit to a color-magnitude (HR) diagram corresponds to an apparent size of about 5 arcmin, which corresponds to about 24 light years. So although the vast majority of the cluster's stars are within 8 light years of its center, a significant number lie nearly half again as far from its center.

The second IC added (per Bigourdan) "Minutes of RA are 29". Apparent size 2.3 by 1.5 arcmin.

Apparent size 3.5 arcmin

Apparent size 20 arcmin

Historical Identification: Per Dreyer, NGC 2261 (= GC 1437 = JH 399 = WH IV 2, 1860 RA 06 31 31, NPD 81 08.7) is "bright, very much elongated 300°, northern cometic feature = magnitude 11." The position precesses to RA 06 39 09.9, Dec +08 44 07, almost dead center on the bright southern tip of the nebula listed above, the description fits and there is nothing comparable nearby, so the identification is certain.
Discovery Notes: Gottlieb provides a long list of subsequent observations on his website (parenthetical additions such as this are used to correct typographical errors or add information): "(The third) Lord Rosse and/or assistant George Johnstone Stoney observed NGC 2261 on 22 Dec 1848 and again on 11 Feb 1894. Stoney likely sketched the nebula on 16 Jan 1850 [figure 10, 1850 publication] and noted 'two comparatively dark spaces, one near the vertex and other near the base of the cone.' William Lassell observed and sketched NGC 2261 in March 1853 with his 24-inch equatorial reflector from Malta. He noted, 'the nucleus not stellar, but like the nucleus of the nebula in Andromeda [M31].' Father Angela Secchi published a detailed sketch and description in 1856 using the 9.6" reracotr in Rome. Julius Schmidt discovered the variability of R Mon in 1861 with a 6" refractor. John Mellish reported discovery of a comet on 6 Sep 1915 [Comet Mellish 1915d] as an observer at Yerkes. The discovery was announced at Harvard but quickly retracted when it turned out to be NGC 2261. Mellish conten(d)ed that the nebula had altered its appearance. The following year, while a graduate student at Yerkes Observatory, Hubble discovered the nebula was variable (publishing the fact in his 1924 paper A Variable Nebula), hence the popular nickname. A series of photographs (showing) the changes were taken with the 30" Reynolds reflector between 1916-1920 at the Helwan Observatory in Egypt. This is an unusual bipolar nebula with the second southern jet hidden from view (by dark clouds obscuring the region to the south)."
Physical Information: For now, see the HST link

Apparent size 4 arcmin

Apparent size 2.6 by 2.0 arcmin

The second IC added "Delete 'remarkable!' An extremely large nebula, 3 degrees in diameter, the densest part 12 arcmin southwest of the star 15 Monocerotis (per Barnard and Roberts)". (Per Steinicke, the cluster itself is about 40 arcmin across.) NGC 2264 is part of a complex region in Monoceros consisting of dark absorption nebulae, emission nebulae, reflection nebulae, and the stars that illuminate or outline their structures. At one end, the Cone Nebula is a dense cloud of gas and dust sculpted by stellar winds from an extremely hot, bright star which is completely hidden in visible light by the gas and dust in front of it. Scattered across the nebula are a number of bright stars which look like lights strung on a Christmas tree, with the Cone Nebula at the apex of the tree, and the bright star S Monocerotis and the Fox Fur Nebula near the base. (The Fox Fur nebula is not generally considered a part of NGC 2264, but is certainly an extension of the gas and dust filling the region, as all the stars and clouds of gas and dust lie at about the same 2600 light year distance from us.)
 The field of view below, extending from the Cone nebula at the top to S Monocerotis and the Fox Fur nebula at the bottom, covers about 30 light years. (Image Credits: ESO)

Below, another view more clearly shows the Cone at the top, and the Fox Fur nebula, to the left of the bright star S Monocerotis, at the bottom (T.A. Rector (NRAO/AUI/NSF and NOAO/AURA/NSF) and B.A. Wolpa (NOAO/AURA/NSF))

Below, a HST closeup of the Cone Nebula shows the dense clouds of gas and dust in a region only a couple of light years across (the overall size of the Cone is about 7 light years). The stars near the tip of the Cone are not responsible for its shape. That is sculpted by stellar winds from an extremely bright star, NGC 2264 IRS, first seen in a 1997 Hubble image, and dramatically shown in a more recent Spitzer image, further below. (ACS Science & Engineering Team, NASA)

Below, a Spitzer Space Telescope infrared image showing open cluster NGC 2264. The brilliant star near the Cone nebula is NGC 2264 IRS, the source of the stellar winds sculpting the Cone. Despite its brilliance, this star is completely hidden by the gas and dust in front of it. Only infrared images can penetrate the dust and reveal the star; but when they do, its brilliance dwarfs that of the other stars in the region. (JPL-Caltech, P. S. Teixeira (CfA), NASA)

At the opposite end of NGC 2264 from the Cone nebula, the Fox Fur Nebula, though not technically a part of NGC 2264, reveals a complex structure of clouds of gas and dust. The bluish glow of the gas to its right is caused by light scattered from the nearby star S Monocerotis, which is outside the field of view, but visible in the full-field images at the top of this section. (Jean-Charles Cuillandre (CFHT) & Giovanni Anselmi (Coelum Astronomia), (copyright Hawaiian Starlight, used by permission)

Apparent size 10 arcmin

Apparent size 5 arcmin

The second IC adds (per Delisle Stewart) "Two nebulae close together". Apparent size 1.7 by 1.3 arcmin.

Apparent size 3.4 by 1.8 arcmin. Used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type SAB(rs)bc.

Apparent size 3.0 arcmin.

Apparent size 10 arcmin.

Apparent size 2.1 by 1.4 arcmin

Apparent size 2.4 by 1.6 arcmin

Historical Identification: Per Dreyer, NGC 2273 (= GC 5363, Dun r (1860 RA 06 37 29, NPD 29 00.3) is "faint, small, irregularly round, mottled but not resolved?" The position precesses to RA 06 50 09.5, Dec +60 50 49, almost dead center on the galaxy listed above, the description fits and there is nothing else nearby, so the identification is certain.
Physical Information: Because of its exceptionally bright central core, NGC 2273 is listed as a Seyfert galaxy (type Sy 1-2), but what makes it most interesting is its unusual "ring" structure. Many galaxies have ringlike structures caused by interactions with other galaxies, or with spiral arms overlapping themselves, but NGC 2273 has not only a complex multi-ring structure inside its bright disk, but also two large, fainter "pseudorings" well beyond the easily visible inner region.
 Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 1875 km/sec (and H₀ = 70 km/sec/Mpc), NGC 2273 is about 85 to 90 million light years away, in good agreement with redshift-independent distance estimates of about 70 to 110 million light years. Given that and its apparent size of about 1.1 by 0.8 arcmin for the bright central region, about 2.6 by 1.4 arcmin for the main galaxy (including the inner pseudoring), and about 3.65 by 2.1 arcmin for the outer pseudoring (all sizes from the images below), the bright central region is about 25 to 30 thousand light years across, the inner pseudoring is about 65 thousand light years across, and the outer pseudoring is about 90 to 95 thousand light years across. The galaxy is used by the de Vaucouleurs Atlas of Galaxy Types as an example of galaxy type (RR)SAB(rs)a, the (RR) referring to the two outer rings, and the (rs) referring to the ring and spiral arm structure in the central part of the galaxy.

Apparent size 2.7 by 2.2 arcmin

Apparent size 2.7 by 1.2 arcmin

Apparent size 1.2 by 1.1 arcmin

Apparent size 1.3 by 0.9 arcmin

Historical Identification: Per Dreyer, NGC 2276 (= GC 5364, Tempel list I (#20), Winnecke, 1860 RA 06 38 31, NPD 04 02) is "faint, 60 arcsec (wide), a little brighter middle." The position precesses to RA 07 27 12.9, Dec +85 45 17, almost dead center on the galaxy listed above, the description fits and the only other object nearby is accounted for by NGC 2300, so the identification is certain.
Usage By The Arp Atlas: NGC 2276 is used by the Arp Atlas of Peculiar Galaxies as an example of a spiral galaxy with one heavy arm, with the note "Tubular arm, straight at first, then bent. Secondary arm from straight portion." It is also used (as Arp 114, with NGC 2300) as an example of an elliptical galaxy (NGC 2300) close to and perturbing a spiral galaxy (NGC 2276), with the note "Spiral somewhat pec., may be perturbed. See No. 25."
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 2820 km/sec (and H₀ = 70 km/sec/Mpc), NGC 2276 is about 130 to 135 million light years away, in reasonable agreement with redshift-independent distance estimates of about 70 to 125 million light years. However, its eastern region is apparently being distorted by NGC 2300, which has a considerably lower recessional velocity, and is almost certainly no more than 110 million light years distant (though the HST press release lists a distance of 120 million light-years for NGC 2276, such statements are always educated guesses, just as the ones here are). Based on all that, the best estimate of its distance is probably in the range of 110 to 115 million light years. Presuming that and given its apparent size of about 2.75 by 2.6 arcmin (from the images below), NGC 2276 is probably about 85 to 90 thousand light years across.
 Aside from its interaction with NGC 2300, NGC 2276 appears to be affected by an interaction with intergalactic gas in the cluster of galaxies that it and NGC 2300 are the largest members of, as its western outline is full of hot, bright young stars. The supposed explanation of that (and one of the main points of the HST press release) is that its 950 km/sec motion away from NGC 2300 is caused by a real motion relative to that galaxy and its surroundings (such a motion is called a "peculiar velocity", to distinguish it from the Hubble Expansion recessional velocity) and that this rapid motion through the intergalactic medium in the cluster is compressing gas near the galaxy's "leading" edge, and creating the aforementioned hot, bright young stars.
 Note that if the above is correct, then the galaxy is not more or less face-on to us, as it appears to be, but is tilted away from us on the western side and toward us on the eastern side, and the compression of the western side by the interaction with intergalactic gas, and the distension of the eastern side by gravitational interaction with NGC 2300, creates the illusion of a more face-on orientation.

Historical Identification: Per Dreyer, NGC 2277 (= GC 5365, d'Arrest, 1860 RA 06 38 36, NPD 56 24.5) is a "cluster, very small, a little rich". The position precesses to RA 06 47 48.0, Dec +33 26 44, less than 0.4 arcmin southeast of the center of the asterism listed above and the description is consistent with those for other asterisms found by d'Arrest, so the identification is reasonably certain.
Discovery Notes: This object is variously listed as only the 13th magnitude star at the northern end of the group, or as the triplet of stars including that star, or as the larger grouping including the double star to the south of the triplet. Bigourdan's observations indicate that he presumed d'Arrest's observation was of only the triplet, and if Dreyer had mentioned Bigourdan in his entry for NGC 2277 I would have chosen to describe this object as only that group, and used its position. But since Bigourdan's observations were not noted by Dreyer and d'Arrest's position is east southeast of the double at the southern end of the group, I have included the double in the listing, and used a position between it and the triplet at the northern end of the group.
Physical Information: A triplet of two brighter stars and a much fainter one a little to the north of a close double consisting of a brighter star and a much fainter companion. There is also a much fainter star just east of the center of the asterism, but it probably contributed little if anything to d'Arrest's impression of the group. The "brighter" stars range from 13th to 14th magnitude, and the entire asterism is fainter than magnitude 12. Apparent size 0.6 by 0.3 arcmin.

Historical Identification: Per Dreyer, NGC 2278 (= GC 5366, d'Arrest, 1860 RA 06 39 03, NPD 56 26.8) is "very faint, very small".

Historical Identification: Per Dreyer, NGC 2279 (Bigourdan (list I #24), 1860 RA 06 39 13, NPD 56 27.1) is "very faint, very small, stellar nucleus".

Historical Identification: Per Dreyer, NGC 2280 (= GC 1450 = JH 3062, 1860 RA 06 39 17, NPD 117 30.1) is "pretty faint, pretty large, a little extended, gradually brighter middle". The position precesses to RA 06 44 51.2, Dec -27 38 38, on the eastern outline of the galaxy listed above and the description fits, so the identification is certain.
Physical Information: Apparent size 6.3 by 3.0? arcmin

Historical Identification: Per Dreyer, NGC 2281 (= GC 1451 = WH VIII 71, 1860 RA 06 39 31, NPD 48 47.3) is a "cluster, pretty rich, very little compressed, stars pretty large". The position precesses to RA 06 49 21.6, Dec +41 03 41, about a minute of time east of the cluster listed above, but the description fits and there is nothing similar nearby, so the identification is certain.
Discovery Notes: William Herschel's VIII 71 was observed by him on Mar 4, 1788; but per Steinicke, Herschel had already observed the cluster (but not recorded it as such) during his earlier studies of double stars, whence the date of discovery shown above.
Physical Information: Apparent size 18 arcmin.

Historical Identification: Per Dreyer, NGC 2282 (Barnard, 1860 RA 06 39 37, NPD 88 32.0) is a "10th magnitude star in faint, round nebulosity". The position precesses to RA 06 46 51.7, Dec +01 19 14, just north of 10th magnitude HD 289120 and near the center of the nebula listed above, so the identification is certain.
Additional Note: One of the primary sources for this catalog incorrectly lists OCL 535 as the cluster lighting up NGC 2282, but that cluster lies about half a degree away from the NGC object, so for a long time this entry stated that the identification must be wrong, and although I have now added its correct identification as OCL 535.1, it seems appropriate to note the possibility of running into such misidentifications, and to retain the entry following this one, which shows the actual OCL 535.
Physical Information: NGC 2282 is a 3.0 by 3.0 arcmin reflection nebula lit up by the cluster of stars (OCL 535.1) located within its dusty environs. However, as shown in the images below the reflection nebula is part of a substantially larger region (almost 6 arcmin across) that contains additional reflection nebulae and clouds of obscuring dust. The cluster and associated nebula are about 5500 light years away, which makes the central 3 arcmin wide region about 5 light years across, and the larger 6 arcmin wide region about twice that size. The age of the cluster is estimated at 5 to 10 million years.

Explanatory Note: In some places the cluster in NGC 228 is incorrectly listed as OCL 535 (it is actually OCL 535.1, as noted in the entry for the NGC object), and it therefore seems appropriate to also show the actual OCL 535, and its position relative to NGC 2282 and OCL 535.1.
Physical Information: About 50 to 100 stars scattered across a region about 7 arcmin across.

Apparent size 3.6 by 2.7 arcmin

Apparent size 15 arcmin

Per Dreyer, NGC 2287 (= Flamsteed, Legentil, M14, 1860 RA 06 41 00, NPD 110 36.0) is a "cluster, very large, bright, a little compressed, stars from 8th magnitude". The reference to M14 is wrong, and was corrected in the first IC, which stated "For M14 read M41". Apparent size 39 arcmin.

Apparent size 0.4 by 0.2 arcmin

Apparent size 1.1 by 0.6 arcmin

Apparent size 1.2 by 0.7 arcmin

Apparent size 1.0 by 0.8 arcmin

The second IC lists a corrected position (per Howe) of RA 06 42 03, NPD 116 35.6. Apparent size 4.0 by 3.5 arcmin. Less than an arcmin from NGC 2293.

The second IC lists a corrected position (per Howe) of RA 06 42 06, NPD 116 36.1. Apparent size 4.0 by 3.2 arcmin. Less than an arcmin from NGC 2292.

Apparent size 0.8 by 0.4 arcmin

The second IC lists a corrected RA (per Howe) of RA 06 41 47, and adds "the double nebula is east, not west" (the double nebula being NGC 2292 and 2293). Apparent size 2.1 by 0.6 arcin.

(The second IC lists a corrected 1860 RA (per Howe) of RA 06 42 25.) A historical discussion will be posted in the next iteration of this page (as the duplicate listing suggests, there are some unfortunate complications). Although the object has a PGC listing, its recessional velocity is close to zero, and at least two studies (by Clemens and Takata) verify that it is an object within our own galaxy, and almost certainly a reflection nebula. The nearly star-free region to the north of the nebula is an absorption nebula, and NGC 2296 is probably part of the same extended cloud, lit up by the bright star hidden within it. Apparent size 1.1 by 0.8 arcmin.

Apparent size 1.9 by 1.5 arcmin

Apparent size 5.0 arcmin

(this entry will only contain historical information; for physical data and images see NGC 2302)