Why is the universe expanding at an ever-increasing rate? This is one of the most exciting yet unresolved questions in modern ...

Our universe appears to be doing so now, which means that over time more and more stars are disappearing outside of our view.

There's a reason why faster-than-light travel has remained a fixture in sci-fi for well over a century, after all. Space is very, very big, and humanity has always dreamed of venturing out very, very ...

The story begins with the black hole information paradox. According to relativity, anything that falls into a black hole is ...

For the first time, physicists have simulated what objects moving near the speed of light would look like — an optical ...

Planets that orbit white dwarf stars should be too hot to host alien life, theories suggest. But a new study accounting for ...

Astronomers have captured the first radio image of two supermassive black holes orbiting each other within the quasar OJ287, ...

Deep in the core of most galaxies, hidden by spinning clouds of gas and dust, black holes spin like cosmic engines. These ...

Time is not absolute, and Einstein argued that different observers experience the present differently depending on relativity ...

Gravitational waves are energy-carrying waves produced by the acceleration or disturbance of massive objects. These waves, ...

Astronomers studying the supermassive black hole M87*, a behemoth six and a half billion times the mass of the Sun, have uncovered a new way these cosmic monsters unleash their power.