NGC 6331

NGC 6331 is an elliptical galaxy in the constellation Ursa Minor about 738 million ly from Earth. It spans roughly 220,000 ly, about 2.2 times the width of our Milky Way. The light reaching us tonight left it about 738 million years ago.

Because its light is 738 million ly from home, you are seeing NGC 6331 as it looked roughly 738 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). Distance computed by gravityfinder from redshift via Hubble's law (H0 = 70 km/s/Mpc).