Ultra-faint dwarf galaxies, cosmic 'ghost towns,' offer new insights into the early universe and star formation.

Leo P, a tiny galaxy, stopped making stars after the universe’s reionization. Unlike most galaxies, it restarted billions of ...

Galaxies like the Milky Way grow by merging with smaller galaxies over billions of years, unlike dwarf galaxies, which have long been thought to lack the heft to attract mass and grow in the same way.

Planets around other stars need to be prepared for extreme weather conditions, according to a new study from NASA's Chandra X ...

Pluto may have got romantic to capture its largest moon, colliding and engaging in a passionate but icy 10 hour kiss with ...