Based on a recessional velocity of 4935 km/sec, IC 550 is about 230 million light years away. Given that and its apparent size of 1.05 by 0.9 arcmin, it is about 70 thousand light years across.

Apparent size 0.95 by 0.65 arcmin.

Apparent size 1.3 by 0.65 arcmin.

Apparent size 1.5 by 1.15 arcmin.

Per Dreyer, IC 554 (Swift list X (#1), 1860 RA 09 34 13, NPD 76 55.9) is "most extremely faint, extremely small, almost stellar". The position precesses to RA 09 41 47.9, Dec +12 26 01 (whence the position above), but there is nothing there. It is generally assumed that Swift actually observed Javelle's IC 555, and simply made an error of 10 arcmin in its declination. However, aside from the fact that this would still put Swift's position well to the southwest of IC 555, the descriptions of the two objects are completely different. So it seems far more likely that Swift observed a different, fainter galaxy (in which case he would still have had to make a large error in its position), or mistook a faint stellar object for a nebula (which, given his description of the object seems by far the most likely, but since there are no obvious stellar matches near his position, is still not at all certain). Which if any of the possibilities might be correct is a mystery, as there is no reasonable alteration of Swift's position that fits any of them; so the best description of IC 554 appears to be, as noted above, "lost or nonexistent".

Per Dreyer, IC 555 (Javelle #167, 1860 RA 09 34 20, NPD 77 04.3) is "pretty bright, very small, round, brighter middle". The position precesses to RA 09 41 54.6, Dec +12 17 37, just west of the galaxy listed above, so the identification is certain. As discussed in the entry for IC 554, that is generally considered a duplicate of IC 555, and as a result some references list PGC 27716 as IC 554, and others as IC 555. Since Javelle's accurate position makes the identification certain, and Swift's completely different position makes it merely a very remote possibility, I have chosen to use IC 555 as the designation for PGC 27716; but the reader should be aware that they may encounter the same galaxy identified (or more likely misidentified) as IC 554 in other places. Apparent size 1.35 by 0.55 arcmin.

Per Dreyer, IC 556 (Javelle #168, 1860 RA 09 36 09, NPD 78 17.9) is "faint, very small, round, nucleus equivalent to 14th-magnitude star". The position precesses to RA 09 43 40.9, Dec +11 03 48, on the periphery of the galaxy, so the identification is certain. Per Corwin the duplicate listing is due to Herschel's position being poor, but the equivalence of the two listings is not in doubt; so see NGC 2984 for anything else.

Apparent size 1.0 by 0.55 arcmin.

Apparent size 1.2 by 1.15 arcmin.

Apparent size 1.25 by 1.0 arcmin; fainter outer regions encompass 1.6 by 1.3 arcmin.

Apparent size 1.8 by 0.7 arcmin.

Apparent size 0.6 by 0.45 arcmin.

Apparent size 1.3 by 0.3 arcmin.

Apparent size 1.1 by 0.4 arcmin.

Apparent size 1.8 by 0.45 arcmin. (See IC 563 for images.)

Accompanied by a compact companion, but whether there is any actual connection between them is unknown; however, the distorted appearance of IC 565 suggests that they may indeed be physical companions. Apparent size 1.55 by 0.2 arcmin.

Apparent size 0.15 by 0.15 arcmin. Nothing else known, so whether an actual companion of IC 565 (which see for images) or merely an optical double is also unknown; however, the distorted appearance of IC 565 suggests that they may indeed be physical companions.

Apparent size of central galaxy 0.45 by 0.4 arcmin; but outer arms extend as much as 1.4 by 0.75 arcmin.

Per Dreyer, IC 567 (Bigourdan #156, 1860 RA 09 42 57, NPD 76 32) is "very faint, suspected, 2 arcmin from III 52", III 52 being NGC 3024. The position precesses to RA 09 50 31.3, Dec +12 48 55, about 3 arcmin north of NGC 3024, and just over an arcmin west of PGC 1416616. However, that galaxy cannot be Bigourdan's object, because extended objects such as galaxies, which have their light spread out over their entire surface area, look far fainter to visual observers than stars, which have all their light concentrated in a nearly pointlike image. As a result, even though PGC 1416616 looks like a reasonable candidate in modern photographs, Bigourdan could not possibly have seen it with his 12-inch telescope, and what he actually saw must have been one of the faint stars in the region. Which star might be a mystery, if not for the fact that Bigourdan, per his usual practice, published his offsets from NGC 3024 as well as his calculated position. Per Thomson, the calculated position is wrong because the coordinates listed for his comparison star were based on an incorrect catalog position for BD+31 2162; but the offsets from NGC 3024 (6.3 seconds of time east and 1' 17" north of that galaxy) fall almost exactly on the star listed above, making its identity as IC 567 certain.

Based on a recessional velocity of 1335 km/sec, PGC 1416616 is about 60 million light years away. Given that and its apparent size of 0.35 by 0.3 arcmin, it is about 6 thousand light years across. That makes it a dwarf galaxy, and given its lack of any apparent structure, probably a dwarf elliptical.

Apparent size 2.05 by 1.35 arcmin.

Apparent size 0.9 by 0.6 arcmin.

Apparent size 0.6 by 0.45 arcmin.

Per Dreyer, IC 571 (Javelle #653, 1860 RA 09 44 53, NPD 73 34.2) is "pretty bright, small, round, nucleus = 12.5 magnitude star". The position precesses to RA 09 52 32.5, Dec +15 46 30, right on the galaxy, so the identification is certain. Apparent size 0.95 by 0.75 arcmin.

Apparent size 0.55 by 0.55 arcmin.

Per Dreyer, IC 573 (Javelle #171, 1860 RA 09 46 45, NPD 101 49 .6) is "extremely faint, very small, round, very small star close". The position precesses to RA 09 53 33.6, Dec -12 29 04, just west of a pair of galaxies, the brighter southern member of which is almost certainly IC 573, and the fainter northern member (per Corwin) is probably the "very small star close". The duplicate listing with NGC 3058 (which consists of both members of the pair of galaxies) was caused by an error in Leavenworth's NPD. Howe soon noted the error, but Javelle rediscovered the object before Howe's correction was published, and Dreyer was not aware of it when he published the Index Catalog (though he did note the correction in the second Index Catalog). (Since tradition prefers using NGC entries instead of later discoveries, this entry only contains historical information; for anything else see NGC 3058.)

Apparent size 1.3 by 1.0 arcmin.

Historical Identification: Per Dreyer, IC 575 (Javelle #656, 1860 RA 09 47 35, NPD 96 12.0) is "faint, small, round, gradually brighter middle". The position precesses to RA 09 54 33.9, Dec -06 51 34, on the southeastern rim of the nucleus of the galaxy listed above, the description fits and there is nothing else nearby, so the identification is certain.
Physical Information: Based on a recessional velocity of 5975 km/sec (and H₀ = 70 km/sec/Mpc), IC 575 is about 275 to 280 million light years away. Given that and its apparent size of about 0.9 by 0.45 arcmin (from the images below), it is about 70 to 75 thousand light years across. It is used by the Arp Atlas as an example of a galaxy with the appearance of wind effects.

Apparent size 0.65 by 0.55 arcmin.

Apparent size 0.65 by 0.55 arcmin.

Apparent size 1.2 by 0.45 arcmin.

Per Dreyer, IC 579 (Swift list VIII (#50), 1860 RA 09 49 48, NPD 103 29.2) is "pretty faint, pretty small, round". The position precesses to RA 09 56 34.1, Dec -14 09 00 (whence the position above), but there is nothing there, or anywhere near there. As a result some references list the object as lost or nonexistent; however, others identify PGC 28702 as IC 579, so although there is no good reason to believe that it really is the IC object, it is discussed immediately below.

There is no particularly good reason to believe that PGC 28702 is IC 579, but it is listed as such in a number of databases (albeit occasionally with a warning that the identification is very uncertain). The identification is presumably based on the galaxy having roughly the same right ascension as Swift's measurement, and being the brightest object within any reasonable distance from his position. However, in most cases Swift's declinations were far more accurate than his right ascensions, and when his declinations were wrong, they were usually off by a simple multiple of one or ten arcminutes, or of whole or half degrees (errors that would be easy to make by misreading the setting circles on his telescope). The 23 arcmin error in declination required to make PGC 28702 equal to IC 579 would be unique, and although a stretch of the imagination might make it conceivable that the identification is correct, it is far more likely to be wrong. As a result, although its frequent (mis?)identification as IC 579 makes it necessary to mention PGC 28702, this entry is intended as a warning about the probable misidentification, and not an endorsement of it.
   Physical Data: Based on a recessional velocity of 9490 km/sec, PGC 28702 is about 440 million light years away. Given that and its apparent size of 1.1 by 0.35 arcmin, it is about 140 thousand light years across.

Per Dreyer, IC 580 (Javelle #175, 1860 RA 09 50 28, NPD 78 53.7) is "pretty faint, very small, irregular figure". The position precesses to RA 09 57 56.8, Dec +10 26 24, on the northern edge of the galaxy, so the identification is certain. Per Corwin, the duplicate listing was due to an arcmin error in Dreyer's position for NGC 3069 (which see for anything else), some uncertainty on his part as to exactly what he had seen (due to scattered clouds on the night of his discovery), and some confusion on Javelle's part as to which nebulae in the region were already known, and which were 'novae'. If Dreyer's position had been better, he would probably have realized that Javelle's #175 was a duplication of his own discovery; but he did not, so the double listing resulted.

Apparent size 1.0 by 0.6 arcmin.

Apparent size 0.9 by 0.9 arcmin. Apparently a companion of IC 583, but although the two galaxies have similar recessional velocities and are probably at about the same (several hundred million light year) distance from us, their lack of any apparent interaction suggests that they are still millions of light years from each other.

Apparent size 1.1 by 0.25 arcmin. In the same field of view as IC 582, which see for images. The two galaxies have similar recessional velocities, so they are probably at about the same (several hundred million light year) distance from us; but their lack of any apparent interaction suggests that they are still millions of light years from each other.

Apparent size 0.4 by 0.4 arcmin.

Apparent size 1.7 by 0.9 arcmin.

Apparent size 0.8 by 0.75 arcmin.

Apparent size 1.25 by 0.6 arcmin.

Apparent size of outer ring 1.05 by 0.95 arcmin.

Apparent size 1.2 by 0.7 arcmin for outer extensions, 0.7 by 0.4 arcmin for brighter central regions.

Apparent size of PGC 29316 = 0.85 by 0.75 arcmin; of PGC 93102 = 0.8 by 0.55 arcmin.

Per Dreyer, IC 591 (Javelle #177, 1860 RA 09 59 58, NPD 77 02.9) is "pretty faint, small, round". The position precesses to RA 10 07 28.6, Dec +12 16 13, barely to the southeast of the galaxy listed above, so the identification is certain.
Discovery Notes: Although Dreyer credited Javelle with the discovery, the object is thought to have been observed 14 years earlier (as Todd #22) when Todd was pursuing his unsuccessful search for a trans-Neptunian planet. Unfortunately, Todd's published notes are verbatim logbook recordings that are far less organized than the carefully edited and organized publications of most other observers, and an observation quoted by Corwin that is supposedly about Todd 22 is actually a belated note about Todd 21; and Todd's actual description of Todd 22 is far too vague to be certain of what it refers to. So as of July 18, 2015 I doubt that either Todd 21 or 22 have been correctly identified. All I know is that Todd 21 was first observed on Feb 5, 1878 and represents an object somewhere to the east or northeast of Regulus, and well to the east of IC 591 (and therefore cannot be that object), and Todd 22 was first observed on Feb 6, 1878 and represents an object somewhere northwest of Regulus and therefore possibly in the vicinity of IC 591, but barring a small miracle I doubt that I will know what either object is before someone reads this. In any event, Javelle's observation was a completely independent discovery, accurately measured, and clearly the galaxy listed above; so he deserves more credit than anyone else for its discovery, regardless of how things turn out with Todd 21 and 22. (Note to self, before finalize: Steinicke also lists Todd 22 as IC 591, probably based on the same incorrect interpretation of Todd's paper, but gives an incorrect date as well; so do not change the date above when doing a final check of discovery data.)
Physical Information: Apparent size 1.1 by 0.7 arcmin?

Apparent size 1.0 by 0.65 arcmin.

Apparent size 0.8 by 0.6 arcmin.

Apparent size 1.1 by 0.55 arcmin.

Apparent size 0.95 by 0.65 arcmin.

Apparent size 0.95 by 0.3 arcmin.

Apparent size 0.9 by 0.3 arcmin.

Apparent size 1.65 by 0.6 arcmin.

Apparent size 1.3 by 0.3 arcmin.