IC 3946

IC 3946 is a lenticular galaxy in the constellation Coma Berenices about 276 million ly from Earth. It spans roughly 69,000 ly, about 69% of our Milky Way's width. It is receding from us at about 5,995 km/s.

Because its light is 276 million ly from home, you are seeing IC 3946 as it looked roughly 276 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.

Source: structural data (position, morphology, brightness, redshift) from OpenNGC (CC BY-SA). Recession velocity from RC3 (de Vaucouleurs et al. 1991, via NASA/HEASARC, public domain). Distance computed by gravityfinder from redshift via Hubble's law (H0 = 70 km/s/Mpc).