IC 3146
IC 3146 is a spiral galaxy in the constellation Coma Berenices about 347 million ly from Earth. It spans roughly 51,000 ly, about 51% of our Milky Way's width. The light reaching us tonight left it about 347 million years ago.
Illustration from its catalogued shape, not a photograph
Because its light is 347 million ly from home, you are seeing IC 3146 as it looked roughly 347 million years ago. The photons left before that much of history had passed, and are only now reaching us. This distance is estimated from the galaxy's redshift, so the lookback time is approximate.
apartIC 3112Barred spiral8.9 million ly
apartIC 3141Lenticular10 million ly
apartIC 3185Barred spiral12 million ly
apartIC 3262Barred spiral13 million ly
apartIC 3193Barred spiral14 million ly
apart
Source: structural data (position, morphology, brightness, redshift) from OpenNGC (CC BY-SA). Distance computed by gravityfinder from redshift via Hubble's law (H0 = 70 km/s/Mpc).