Extreme cosmic events such as colliding black holes or the explosions of stars can cause ripples in spacetime, so-called gravitational waves. Their discovery opened a new window into the universe. To ...

Without a constant for dark energy, Albert Einstein’s original fear could be true: that gravity will pull the universe back into itself, leading to a Big Crunch that will reverse or undo the Big ...

Astronomers have discovered that the Small Magellanic Cloud, a nearby dwarf galaxy, is being torn apart by the gravitational ...

Isaac Newton’s approach correctly predicts the gravitational attraction between any two objects but gives no insight into how something here can reach out across empty space and pull on ...

This is enough, he claims, to overcome the pull of gravity without any exhaust or fuel. He describes the force the gravity-defying propulsion system creates as a “New Force” not currently ...

With no outward pressure from fusion to counterbalance gravity's inward pull, the star condenses and collapses in upon itself. Despite their small diameters—about 12.5 miles (20 kilometers ...

Black holes are objects with an intense gravitational pull so strong that not even beams of light, the fastest things in the universe, can escape. This makes them impossible to see directly ...