Page last updated July 31, 2021
PGC 8580 (= PGC 600934 = ESO 298-023)
A magnitude 14.5(?) spiral galaxy (type S/IABm:) in Fornax (RA 02 14 27.6, Dec -39 11 07)
Note About Classification: The type is taken from the Spitzer Survey of Stellar Structure in Galaxies. The colon on the "m" means that part of the classification is uncertain, and since the "m" itself means that the galaxy is poorly organized, it's hard to decide whether it's a spiral or irregular galaxy (hence the "S/I").
 Above, a 12 arcmin wide DSS image centered on PGC 8320
PGC 8802 (= Arp 10)
A 13th-magnitude spiral galaxy (type (R)Sb?) in Cetus (RA 02 18 26.4, Dec +05 39 14)
Based on recessional velocity of 9110 km/sec, about 400 million light years away. Given that and apparent size of 1.5 by 1.5 arcmin, about 175 thousand light years across. The galaxy is one of six chosen by Halton Arp for his Atlas of Peculiar Galaxies as an example of spiral galaxies with split arms, hence its designation as Arp 10.
 Above, a 2.4 arcmin wide closeup of PGC 8802 Below, a 12 arcmin wide region centered on the galaxy

PGC 8961 (with PGC 8970 = Arp 273)
A 13th-(B)magnitude spiral galaxy (type SA(s)b pec) in Andromeda (RA 02 21 28.7, Dec +39 22 32)
PGC 8961 and 8970 form an interacting pair of spiral galaxies, also known as Arp 273. Both galaxies are considerably distorted by their interaction, but PGC 8961's spectacular arms and brilliant clouds of hot, bright young stars caused by the interaction are more obvious because it is nearly face-on to our line of sight; while PGC 8970's form is more edge-on, and appears more a chaotic mess than its companion. (In some ways this is similar to the more elegant M81 and more distorted M82, a more widely separated pair far closer to us.) Based on a recessional velocity of 7565 km/sec, PGC 8961 is about 350 million light years away. Given that and its apparent size of 2.2 by 1.4 arcmin, it is about 225 thousand light years across. This makes it more than twice the diameter and about ten times the volume (and most likely, mass) of our Milky Way galaxy.
 Above, an HST image of Arp 273 (Image Credits: NASA, ESA, Hubble Heritage Team (STScI / AURA)) Below, a labeled version of the same image
 Below, a 12 arcmin wide region centered on Arp 273

PGC 8970 (with PGC 8961 = Arp 273)
A 15th-(B)magnitude barred spiral galaxy (type SB(s)a pec) in Andromeda (RA 02 21 32.6, Dec +39 21 25)
PGC 8970 and 8961 form an interacting pair of spiral galaxies, also known as Arp 273. Both galaxies are considerably distorted by their interaction, but PGC 8961's spectacular arms and brilliant clouds of hot, bright young stars caused by the interaction are more obvious because it is nearly face-on to our line of sight; while PGC 8970's form is more edge-on, and appears more a chaotic mess than its companion. (In some ways this is similar to the more elegant M81 and more distorted M82, a more widely separated pair far closer to us.) Based on a recessional velocity of 7335 km/sec, PGC 8970 is about 340 million light years away (although a second recessional velocity measurement of 7780 km/sec would put it about 360 million light years away; and regardless of its recessional velocity, its distance must be nearly identical to that of its companion). Given that and its apparent size of 1.5 by 0.4 arcmin, it is about 150 thousand light years across. For images of the pair, see PGC 8961.
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