Chandra

Astronomers have pinpointed five pairs of merging black holes using three different space and ground-based instruments and two sky surveys.

Scientists detected gravitational waves from merging neutron stars. What have they become now?

A new video shows the explosive reaction when a dense stellar corpse sucks up material from a pulsating dead star.

A wave of hot gas twice as wide as the Milky Way galaxy roils the nearby Perseus galaxy cluster, a new study indicates.

A supermassive black hole has been gobbling up a star for more than a decade — about 10 times longer than any previously known such meal, a new study finds.

Astronomers have discovered an immense surge of energy coming from a cosmic particle accelerator located about 2 billion light years from Earth.

Huge numbers of supermassive black holes are visible in a stunning new photo that astronomers said is the deepest X-ray image of the sky ever captured.

A decades-old galactic mystery has just been solved — new research has revealed why a distant galaxy has brightened and dimmed like a flickering candle flame over the last 30 years.