Astronomers watched a distant star dim for months and found a metal-rich cloud that may be the aftermath of a massive ...
Astronomers detect a massive metal-rich cloud orbiting an unseen companion of star J0705+0612. Observations reveal its size, composition, and possible origin from a planetary collision.
Planetary systems begin in chaos. In their primitive form, many rocky and icy objects are careening through space, smashing into each other, breaking apart, and accumulating to form planets, moons, ...