NGC 4645B

NGC 4645B is a lenticular galaxy in the constellation Centaurus about 104 million ly from Earth. It spans roughly 65,000 ly, about 65% of our Milky Way's width. It is receding from us at about 2,579 km/s.

Because its light is 104 million ly from home, you are seeing NGC 4645B as it looked roughly 104 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).