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Planetary system

Adapted from Wikipedia · Explorer experience

An artist's illustration of a planetary system showing planets orbiting a star, created by NASA.

A planetary system is a special group of objects that stay together because of gravity. These objects move around a star. They can be planets, tiny rocks called asteroids, small natural moons, pieces of ice and rock called comets, and very small pieces called meteoroids. Our own system is called the Solar System. In it, Earth and seven other planets move around the Sun.

Scientists have found many planetary systems that are not our own. These discoveries help us learn about how planets are made and what other worlds might be like.

One exciting part of studying planetary systems is the habitable zone. This is an area where planets might have liquid water on their surfaces. Scientists are very interested in finding and studying planets in these zones.

The Milky Way is a very big galaxy, about 100,000 light-years across. Most of the planets we know are within 2000 light years of Earth. Scientists use special ways to find planets far away, and new telescopes may help us learn even more.

Images

An old scientific drawing showing how Copernicus described the solar system with the Sun and planets moving around it.
An artist’s illustration showing how tiny dust particles come together to form new planets around a young star, with bright light shaping the surrounding gas and dust.
Images of young planetary systems surrounding stars, showing how planets may form.
Astronomers discovered hidden debris disks around young stars using the Hubble Space Telescope. These disks, made of dust from colliding space rocks, help us learn how planets form!
A diagram showing the region of the Milky Way where most known planets are discovered, helping us understand our place in space.
An image of a newly forming planet orbiting the star PDS 70, captured by a telescope.
A stunning view of Earth rising over the Moon, as seen by astronauts during the Apollo 8 mission.
A colorful diagram showing the planets in our solar system, including Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, and Neptune, as captured by NASA spacecraft.
Diagram showing the habitable zone around a star where life might exist.

Related articles

Star
Solar System
Earth
Milky Way

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

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