Page last updated Dec 14, 2019|
A magnitude 15.3 lenticular galaxy (type S0/a) in Sextans (RA 10 50 01.7, Dec -01 52 04)
Physical Information: Based on a recessional velocity of 11215 km/sec (and H0 = 70 km/sec/Mpc), a straightforward calculation indicates that PGC 32442 is about 520 to 525 million light years away, considerably further than a single redshift-independent distance estimate of about 385 million light years. 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 500 million light years away at the time the light by which we see it was emitted, about 510 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 0.4 by 0.15 arcmin (from the images below), the galaxy is about 55 to 60 thousand light years across.
Note About HST Image (Not Shown): An HST image of interstellar Comet Borisov happened to show PGC 32442 just to the side of this galaxy. Because the image was taken following the motion of the comet, the core of the galaxy was smeared into what appears to be a bar; for that reason, it is not shown here. However, the image did show that the galaxy had a more complex structure than an ordinary type S0 galaxy, so the type given above is almost certainly correct.
Above, a 12 arcmin wide SDSS image centered on PGC 32442
Below, a 0.5 arcmin wide SDSS image of the galaxy