Page last updated Dec 24, 2015|
A magnitude 16(?) spiral galaxy (type Sb?) in Eridanus (RA 02 36 33.8, Dec -41 52 30)
Physical Information: Based on a recessional velocity of 14400 km/sec, a straightforward calculation indicates that PGC 102500 is about 670 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 630 to 635 million light years away at the time the light by which we see it was emitted, about 650 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 0.1 arcmin, the galaxy is about 80 thousand light years across.
Above, a 12 arcmin wide DSS image centered on PGC 102500
Below, a 0.6 arcmin wide DSS image of the galaxy