NGC 5821

NGC 5821 is a spiral galaxy in the constellation Boötes about 158 million ly from Earth. It spans roughly 68,000 ly, about 68% of our Milky Way's width. It is receding from us at about 3,337 km/s.

Because its light is 158 million ly from home, you are seeing NGC 5821 as it looked roughly 158 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).