NGC 3139

NGC 3139 is a lenticular galaxy in the constellation Hydra about 430 million ly from Earth. It spans roughly 150,000 ly, about 1.5 times the width of our Milky Way. The light reaching us tonight left it about 430 million years ago.

Because its light is 430 million ly from home, you are seeing NGC 3139 as it looked roughly 430 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).