IC 4537

IC 4537 is a lenticular galaxy in the constellation Serpens about 758 million ly from Earth. It spans roughly 170,000 ly, about 1.7 times the width of our Milky Way. The light reaching us tonight left it about 758 million years ago.

Because its light is 758 million ly from home, you are seeing IC 4537 as it looked roughly 758 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).