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Ocean world

Adapted from Wikipedia · Explorer experience

A view of Earth from space taken by the Apollo 11 astronauts, showing our beautiful planet from orbit.

Ocean Worlds

An ocean world is a special place — either a planet or a moon — that has a lot of water. This water might be on the surface, like the oceans on Earth, or hidden deep inside under layers of ice. Scientists are very excited about ocean worlds because they might be places where life could exist.

Earth is the only place we know right now that has big oceans of liquid water on its surface. But we think some of Jupiter's moons, like Europa and Ganymede, and some of Saturn's moons, like Enceladus and Titan, might have hidden oceans inside them. These oceans could be very deep and might even be made of different kinds of water, like a mix of water and ammonia.

Scientists study these faraway oceans to learn more about how planets form and change. They also want to know if these places could support life. In 2020, scientists from NASA shared that planets with oceans might be very common in our big Milky Way galaxy. They figured this out using special math tools.

Ocean worlds come in many forms. Some might have oceans just like Earth's, while others could have very deep oceans, maybe even hundreds of miles deep! Scientists look for signs of water by studying the way these planets and moons move and by using special space machines called space probes.

Learning about ocean worlds helps us understand our own planet better and shows us how common water might be in space. Who knows? Maybe one day we will visit an ocean world and discover amazing new things!

Images

The Crab Nebula is the remnant of a star that exploded long ago. This beautiful image shows colorful clouds of gas and a spinning neutron star at its center, captured by the Hubble Space Telescope.
A beautiful painting of our Milky Way galaxy, used to show the area searched by the Kepler Mission.
Artist concept of water-world exoplanets—planets orbiting other stars that may contain vast amounts of water.
A colorful diagram showing different kinds of planets discovered in space by the Kepler telescope, compared to planets found by other methods.
A stunning space image showing the protoplanetary disk around the young star HL Tauri, where new planets may be forming.
An artistic illustration of a Hycean planet — a hypothetical world covered in deep oceans and wrapped in a hydrogen atmosphere, which scientists think might be a place to search for life beyond Earth.
Astronomers captured this amazing picture of a planet just being born around a star called PDS 70, showing us how new worlds form in space!
A Hubble Space Telescope image showing stars and potential exoplanet locations in the Milky Way galaxy.
A beautiful butterfly called Issoria lathonia resting on a flower.
A stunning view of Earth rising over the lunar horizon, captured by astronauts during the Apollo 8 mission in 1968.

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

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