NGC 1584
NGC 1584 is an elliptical galaxy in the constellation Eridanus about 425 million ly from Earth. It spans roughly 120,000 ly, about the width of our Milky Way. The light reaching us tonight left it about 425 million years ago.
Illustration from its catalogued shape, not a photograph
Because its light is 425 million ly from home, you are seeing NGC 1584 as it looked roughly 425 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.
apartNGC 1565Spiral16 million ly
apartNGC 1561Elliptical16 million ly
apartNGC 1564Lenticular17 million ly
apartNGC 1562Lenticular18 million ly
apartNGC 1630Lenticular19 million ly
apart
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).