The supermassive black hole at the center of the Milky Way is the most extreme astrophysical object located within a million light-years of Earth. With an estimated four million solar masses, it's the ...

All bodies in a given gravitational field are thought to fall with the same acceleration. This idea, known as the equivalence principle, is central to our understanding of gravitational physics. It ...

Einstein’s general theory of relativity can be summed up in just 12 words: “Space-time tells matter how to move; matter tells space-time how to curve”. But this short description from the physicist ...

Some habitable worlds orbiting dead stars could be kept alive for aeons thanks to a quirk of Einstein’s theory of gravity ...