Sep 25, 2025 · The answer is gravity: an invisible force that pulls objects toward each other. Earth's gravity is what keeps you on the ground and what makes things fall. An animation of …

Sep 25, 2025 · Before this, just about everything we knew about the universe came from studying waves of light. Now we have a new way to learn about the universe—by studying waves of …

Sep 25, 2025 · We know that the Moon has almost no atmosphere and only about one-sixth of Earth’s gravity. We even know that there is quite a bit of frozen water tucked away in craters …

Sep 25, 2025 · Dark matter is stuff in space that has gravity, but it is invisible and isn’t like anything else we know about. Dark matter makes up about 27% of the universe.

Sep 25, 2025 · Satellites that orbit close to Earth feel a stronger tug of Earth’s gravity. To stay in orbit, they must travel faster than a satellite orbiting farther away.

Sep 25, 2025 · Space is a pretty dark place. Even so, some areas are darker than others. Nothing is darker than a black hole. A black hole is an area of such immense gravity that nothing—not …

Sep 25, 2025 · NASA’s Galileo mission found good evidence that underneath this rock-hard, icy crust there is a huge, salty, liquid ocean. Since there are lots of tiny creatures that live in very …

Sep 25, 2025 · A galaxy is held together by gravity. Our galaxy, the Milky Way, also has a supermassive black hole in the middle. When you look up at stars in the night sky, you’re …

Sep 25, 2025 · When you stand on a scale, what it’s actually doing is measuring how hard Earth’s gravity is pulling on you. If you were to step onto a scale on another planet, it would say …

Sep 25, 2025 · What Is Gravity? Gravity is the force by which a planet or other body draws objects toward its center. explore What Is a Black Hole? Space Place in a Snap tackles this …