The original Principal Galaxies Catalog contained 73,197 entries. Subsequent revisions have increased this to more than three million entries. I have no intention of covering all of those entries on this site, but there needs to be a place to list or discuss (if needed) any PGC entries referred to elsewhere, so this page (or if it grows too large some group of pages based on this page) will eventually discuss all such entries with PGC designations of 130,000 to 999,999.

Physical Information: Apparent size 1.35 by 1.25 arcmin, including faint outer arms.

Based on recessional velocity of 11390 km/sec, about 500 million light years away. Given that and starlike apparent size of 0.07 arcmin, perhaps 10 thousand light years across. In nearly the same direction as PGC 138157, which see for image.

Based on recessional velocity of 26080 km/sec, about 1.15 billion light years away. Given that and starlike apparent size of 0.07 arcmin, perhaps 20 thousand light years across.

Listed in NED as SDSSJ122802.01+114049.6. Based on recessional velocity of 20820 km/sec, about 930 million light years away. Given that and apparent size of 0.3 by 0.15 arcmin, about 80 thousand light years across.

Based on recessional velocity of 6055 km/sec, about 270 million light years away. Given that and apparent size of 0.5 by 0.5 arcmin, about 40 thousand light years across.

Physical Information: Based on a recessional velocity relative to the Cosmic Background Radiation of 13120 km/sec (and H₀ = 70 km/sec/Mpc), a straightforward calculation indicates that PGC 160085 is about 610 million light-years away. However, for objects at such distances we should take into account the expansion of the Universe during the time it took their light to reach us. Doing that shows that the galaxy was about 580 million light-years away at the time the light by which we see it was emitted, about 590 to 595 million years ago (the difference between the two numbers being due to the expansion of the intervening space during the light-travel time). Given that and its apparent size of about 0.45 by 0.45 arcmin (from the images below), the galaxy is about 75 thousand light-years across.
(Lack Of) Relationship To NGC 5728: Normally, PGC 160085 might be listed on the page for NGC 5728, as an apparent companion; but it is listed here instead, because it is a much more distant background galaxy, and therefore has no relationship to the far nearer galaxy.
Classification Note: The galaxy has a very peculiar structure, obviously caused by some kind of collision or gravitational interaction; in fact, although there is no way to tell from currently available data, the elongated object on the northwestern side of the galaxy may well be another galaxy which is the cause of the disturbance to PGC 160085.

Identified in NED as VPC 559. Although the Virgo Photometry Catalogue is a list of galaxies in the area of the Virgo Cluster of galaxies, PGC 169337 is not a member of that cluster, but a very distant background object. Based on its recessional velocity of 26880 km/sec, it is about 1.2 billion light years away. Given that and its apparent size of 0.3 by 0.25 arcmin, it is about 100 thousand light years across.

Listed in NED as VPC 587. Although the Virgo Photometry Catalogue is a list of galaxies in the area of the Virgo Cluster of galaxies, PGC 169351 is not a member of that cluster, but a very distant background object. Based on its recessional velocity of 25730 km/sec, it is about 1.15 billion light years away. Given that and its apparent size of 0.25 by 0.15 arcmin, it is about 90 thousand light years across. PGC 169351 and 169360 have similar recessional velocities, and are probably about the same distance from us, so there is a chance that they are gravitationally bound.

Listed in NED as VPC 604. Although the Virgo Photometry Catalogue is a list of galaxies in the area of the Virgo Cluster of galaxies, PGC 169360 is not a member of that cluster, but a very distant background object. Based on its recessional velocity of 25985 km/sec, it is about 1,15 billion light years away. Given that and its apparent size of 0.2 by 0.2 arcmin, it is about 70 thousand light years across. PGC 169360 and 169351 have similar recessional velocities, and are probably about the same distance from us, so there is a chance that they are gravitationally bound.

Listed in NED as SDSSJ122841.89+113816.7. Based on recessional velocity of 26085 km/sec, about 1.15 billion light years away. Given that and apparent size of 0.15 by 0.15 arcmin, about 60 thousand light years across. Given its proximity to PGC 169365 in direction and distance (as inferred from their recessional velocities), there is a good chance that the galaxies are gravitationally bound.

Listed in NED as VPC 614. Although the Virgo Photometry Catalogue is a list of galaxies in the area of the Virgo Cluster of galaxies, PGC 169365 is not a member of that cluster, but a very distant background object. Based on recessional velocity of 26010 km/sec, about 1.15 billion light years away. Given that and apparent size of 0.3 by 0.1 arcmin, about 100 thousand light years across. Given its proximity to PGC 169363 (which see for views of the galaxies) in direction and distance (as inferred from their recessional velocities), there is a good chance that the galaxies are gravitationally bound.

Based on its recessional velocity of 26130 km/sec, about 1.15 billion light years away. Given that and its apparent size of 0.25 by 0.2 arcmin, about 80 thousand light years across. Given its proximity to PGC 169363 and 169365 in direction and distance (as inferred from their recessional velocities), there is a good chance that the galaxies are gravitationally bound.

Historical Misidentification: As noted in the entry for NGC 3915, this is one of several galaxies that have been misidentified as that almost certainly lost or nonexistent object (which see for a discussion of that topic). As a result, this entry serves not only as a discussion of PGC 170172, but also as a warning about the misidentification.
Physical Information: Based on a recessional velocity relative to the Cosmic Microwave Background radiation of 2930 km/sec (and H₀ = 70 km/sec/Mpc), PGC 170172 is about 135 to 140 million light years away. Given that and its apparent size of about 0.36 by 0.32 arcmin (from the images below), the galaxy is about 15 thousand light years across. Based on the unusually bright center of the galaxy, it is possible that it is a Seyfert galaxy.

Apparent size 0.35 by 0.35 arcmin. Nothing else known. Type based on the image below, and given its poor quality, very uncertain.

(Usually referred to as 2MASX J00482185-2507365, but searchable on NED by its PGC listing.) Based on a recessional velocity of 19190 km/sec, a straightforward calculation indicates that the galaxy is about 890 million light years away. However, at such distances, we must take into account the expansion of the Universe during the time the galaxy's light took to reach us. Doing so shows that the galaxy was 830 million light years away when the light by which we see it was emitted, 855 million years ago (the difference between the two numbers being due to the expansion of the space between it and us during that time). A Hubble news release (accompanying the closeup image below) states that the galaxy is about 780 million light years away, in reasonable agreement with the redshift distance. Using a distance of about 800 million light years and its apparent size of 0.42 by 0.25 arcmin suggests that PGC 198197 is about 100 thousand light years across (which also agrees with the estimate in the Hubble news release). Perhaps the most interesting feature of the galaxy is its nearly perfect alignment with another galaxy, HKW2009, an 18th-(B)magnitude foreground galaxy which appears about five times smaller, and being closer is suggested as being perhaps a tenth its size, or about 10 thousand light years across. The overlapping of the galaxies provides an unusually detailed view of the dusty outer regions of the foreground galaxy, and suggests that they extend several times as far from its core as the visible stars in its spiral structure (so that it is actually several times larger than it appears). It has been long known that many (if not most) galaxies have extensive "haloes" filled with gas, dust and other unseen material (such as "dark matter"), but it is unusual to find such an easy and exact way to study those regions.

Physical Information: An apparent companion or optical double with IC 197, so covered in the entry after that.

Physical Information: Vr 4490 km/sec (see IC 308 for a wide-field image)

Physical Information: Based on a recessional velocity of 2220 km/sec, NGC 3687 is 100 to 105 million light years away. Given that and its apparent size of about 0.3 by 0.2 arcmin, it is about 9 thousand light years across. The galaxy is listed in NED as 2MASXJ11280416+2930387, and as a starburst galaxy. Given the fact that its radial velocity is less than 300 km/sec smaller than that of its apparent companion (NGC 3687), it is possible that they are physical companions, and the somewhat peculiar appearance of the larger galaxy and the classification of the smaller galaxy as a starburst galaxy may at least indicate some kind of past interaction between the two; but I can find no mention of the possibility that they are connected, so barring further developments they should probably be treated as merely an optical double with a separation of 10 to 20 million light years, and their "peculiarities" as part of the normal range of galaxy types.

Physical Information: Based on a recessional velocity of 8540 km/sec, a straightforward calculation indicates that PGC 214261 is about 395 to 400 million light years away. However, for objects at such distances we should take into account the expansion of the Universe during the time it took their light to reach us. Doing that shows that the galaxy was about 385 million light years away at the time the light by which we see it was emitted, about 390 million years ago (the difference between the two numbers being due to the expansion of the intervening space during the light-travel time). Given that and its apparent size of about 0.85 by 0.25 arcmin, the galaxy is about 95 thousand light years across.

Based on a recessional velocity of 14825 km/sec, a straightforward calculation indicates that PGC 446330 is about 690 million light years away. However, for objects at such distances we should take into account the expansion of the Universe during the time it took their light to reach us. Doing that shows that the galaxy was about 650 million light years away at the time the light by which we see it was emitted, about 665 million years ago (the difference between the two numbers being due to the expansion of the intervening space during the light-travel time). Given that and its apparent size of 0.7 by 0.2 arcmin, the galaxy is about 130 thousand light years across. Since its distance appears similar to that of IC 4917, they may be a physical pair; but there is no obvious interaction between them, so even if a physical pair they are probably a few million light years apart (as in the case of our galaxy and the Andromeda Galaxy).

Listed in NED as 2DFGRSS360Z141. Based on a recessional velocity of 41670 km/sec, a straightforward calculation indicates that PGC 723295 is about 1.8 billion light years away. However, for such a distant object, we need to take into account the expansion of the Universe during its light's journey. Doing so shows that the galaxy was about 1.6 billion light years away when the light by which we see it was emitted, about 1.7 billion years ago (the difference between the two numbers being due to the Universal expansion during that time). Given that and its apparent size of 0.27 by 0.14 arcmin, it is about 125 thousand light years across.

Listed in NED as 2DFGRSS359Z122. Based on a recessional velocity of 18375 km/sec, a straightforward calculation indicates that PGC 724741 is about 820 million light years away. However, for such a distant object, we need to take into account the expansion of the Universe during its light's journey. Doing so shows that the galaxy was about 765 million light years away when the light by which we see it was emitted, about 785 million years ago (the difference between the two numbers being due to the Universal expansion during that time). Given that and its apparent size of 0.23 by 0.18 arcmin, it is about 50 thousand light years across.

Listed in NED as 2DFGRSS278Z243. Based on a recessional velocity of 41820 km/sec, a straightforward calculation indicates that PGC 724741 is about 1.85 billion light years away. However, for such a distant object, we need to take into account the expansion of the Universe during its light's journey. Doing so shows that the galaxy was about 1.6 billion light years away when the light by which we see it was emitted, about 1.7 billion years ago (the difference between the two numbers being due to the Universal expansion during that time). Given that and its apparent size of 0.27 by 0.18 arcmin, it is about 125 thousand light years across. For images, see PGC 724751.

Listed in NED as APMUKS(BJ) B001420.48-134614.0, with coordinates and apparent size (0.13 by 0.11 arcmin) suggesting that it is a very faint extension of PGC 937493. The DSS image does show a faint smudge which may be a separate object, but the SDSS image does not; so the object may not exist, or may be a duplicate listing of PGC 937493 (which see).

Listed in NED as APMUKS(BJ) B001414.17-134520.7. Apparent size 0.6 by 0.3 arcmin; nothing else available. "Associated" with PGC 937463, which may be a faint extension of the spiral, an independent galaxy, a nonexistent object, or a duplicate listing.

PGC identification is certain. Mousing over the Wikisky field near NGC 17 yields an identification as PGC 956278. Using the object's coordinates yields a NED listing for 2MASXJ00110416-1211586; HyperLeda then cross-references the object as PGC 956278, confirming the Wikisky identification. Note: searching for that name in Wikisky shows a completely different galaxy (PGC 56278); this is a common truncation error in the Wikisky search engine. Apparent size 0.45 by 0.3 arcmins; nothing else available.

PGC identification is based on HyperLeda, and mousing over the Wikisky field near NGC 17. Not listed in NED. Note: searching for PGC 957826 in Wikisky shows a completely different galaxy (PGC 57826), a common truncation error in the Wikisky search engine; use its coordinates for the correct result. Apparent size 0.42 by 0.25 arcmins; nothing else available.