Swift is a NASA satellite designed to spot gamma-ray bursts, the most powerful explosions in the Universe. What kinds of dynamic cosmic activity can release such high-energy wavelengths of light?

Although neighboring Andromeda Galaxy may look tranquil, scientists are realizing the extent of its tumultuous history.

For its 19th anniversary, the Hubble Space Telescope has shot the peculiar group of galaxies Arp 194.

Astronomers have spotted a rare, complex cosmic collision of four galaxy clusters. A spectacular composite image from NASA's Chandra X-Ray Observatory and Hubble Space Telescope revealed the pileup—and its likely source.