Two giant galaxies combine to form a massive ellipse.
Planet-forming particles swarm an unlikely star host.
Plentiful ice in the Saturn system hints at its age.
Astronomers measure how fast a black hole spins.
A river valley found on a distant moon resembles Earth’s Nile.
A giant hole in the dust disk around a star could hold multiple planets.
Students partner with NASA to direct cameras orbiting the Moon.
An enormous galaxy cluster is birthing stars at a furious pace.
NASA’s mission control guided Curiosity to a perfect landing in Gale Crater.
Sky-gazers caught a rare glimpse of Venus framed by the Sun.