"It looks like it has been through some kind of event that caused it to form a lot of stars and then just shut down” ...

Hubble Space Telescope mapped Andromeda, revealing a chaotic history shaped by mergers. A 2.5-billion-pixel mosaic shows 200 ...

"Photographing Andromeda was a herculean task because the galaxy is a much bigger target on the sky than the galaxies Hubble ...