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Gravity

Adapted from Wikipedia · Explorer experience

A stunning view of Earth rising over the Moon, captured by astronauts during the Apollo 8 mission in 1968.

What is Gravity?

Gravity is a special force that pulls things together. It is one of the four main forces in the universe. You feel gravity every day because it keeps you on the ground. Without gravity, you would float away into the sky!

Gravity pulls everything with mass toward other things with mass. The bigger something is, the stronger its pull. That’s why the Earth can keep you from floating up. Even tiny objects pull on each other, but you need very sensitive tools to notice it.

How Gravity Shapes the Universe

Gravity helps make stars, planets, and even big groups of stars called galaxies. In the beginning, gravity pulled together clouds of hydrogen. These clouds became hot and dense, and then they turned into stars! Gravity also helps keep satellites moving around the Earth so we can use them for phones and maps.

Gravity on Earth

On Earth, gravity gives you your weight. It also helps ocean waves move and makes things fall down when you drop them. Gravity is a little weaker at the equator because the Earth spins, but it is strong enough to keep everything from flying off into space.

Fun Gravity Facts

  • The Moon also has gravity, but it is much weaker than Earth’s. If you weigh 50 pounds on Earth, you would only weigh about 6 pounds on the Moon!
  • Gravity keeps the Sun and the planets in their places, making sure they stay in their paths around the Sun.
  • Scientists study gravity to learn more about the universe and even to find hidden parts of space called dark matter.

Images

A physics experiment showing how a ball falls under gravity, captured in slow motion to demonstrate motion principles.
The Crab Nebula: A colorful view of a star's explosion remnant captured by the Hubble Space Telescope.
A stunning view of two interacting galaxies, showing the beautiful dance of stars and space created by the Hubble Space Telescope.
The Leaning Tower of Pisa is an iconic Italian tower famous for its unintended tilt. It’s one of the most visited landmarks in the world!
Portrait of Sir Isaac Newton, a famous scientist from the 17th century.
Animation showing how gravity works through Newton's third law of motion: for every action, there is an equal and opposite reaction.
Aerial view of the LIGO Hanford Observatory, a scientific research facility studying gravitational waves.
The Einstein Cross shows how light from a distant star is bent by gravity, creating four bright images in the sky.
A colorful educational montage of the planets in our solar system, showing Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune.
Historical photograph of stars during a solar eclipse, used to test Einstein's theory of light bending.
An artist's rendering of HE 1523-0901, one of the oldest known stars in our galaxy, located about 7,500 light-years from Earth.

This article is a child-friendly adaptation of the Wikipedia article on Gravity, available under CC BY-SA 4.0.

Images from Wikimedia Commons. Tap any image to view credits and license.