gravity

Here are nine equations that altered the course of history.

Quantum mechanics explains why the electrons can keep spinning indefinitely.

The unusual trio is much more massive and compact than similar systems.

The light they produce wobbles around, making them hard to pin down.

Small bodies like asteroids and comets are shaped more by their geological makeup than by gravity, which molds planets and moons into spheres.

If a super-advanced civilization had to ability to engineer the solar system from scratch, how many planets could they squeeze around the sun?

What would it take to dislodge the moon from its orbit and send it on a collision course with Earth?

A group of physicists has measured gravity using the effects of time dilation — the slowing of time imparted by increased velocity or gravitational force — on atoms.

A tiny galaxy orbiting at the outskirts of the Milky Way appears to have a giant black hole at its center, comparable to that of the much larger Milky Way itself, and scientists don't know why.