Exoplanets

Overview

Most of the exoplanets discovered so far are in a relatively small region of our galaxy, the Milky Way. (“Small” meaning within thousands of light-years of our solar system; one light-year equals 5.88 trillion miles, or 9.46 trillion kilometers.) Even the closest known exoplanet to Earth, Proxima Centauri b, is still about 4 light-years away. We know there are more planets than stars in the galaxy.

By measuring exoplanets’ sizes (diameters) and masses (weights), we can see compositions ranging from rocky (like Earth and Venus) to gas-rich (like Jupiter and Saturn). Some planets may be dominated by water or ice, while others are dominated by iron or carbon. We’ve identified lava worlds covered in molten seas, puffy planets the density of Styrofoam and dense cores of planets still orbiting their stars.

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NASA’s Webb Finds New Evidence for Planet Around Closest Solar Twin

Astronomers using NASA’s James Webb Space Telescope have found strong evidence of a giant planet orbiting a star in the…

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checking out the neighbors

‘Other Stars, Other Worlds’

Is our home — our solar system — unique among all the stars and planets in the Milky Way galaxy? When compared to other planetary systems, are we that different? How much are we alike? This five-part series of animations and stories looks at some of our intriguing galactic neighbors.

Watch and Read ‘Other Stars, Other Worlds’

An artist's rendering shows a small spacecraft in orbit around Earth.

This artist's concept features the nearby star TRAPPIST-1, an ultra-cool dwarf, with seven Earth-sized planets orbiting it. Two of the planets were discovered in 2016 by TRAPPIST (the Transiting Planets and Planetesimals Small Telescope) in Chile. NASA’s Spitzer Space Telescope and several ground-based telescopes uncovered five additional ones. The TRAPPIST-1 system is located about 40 light-years from Earth.

NASA/JPL-Caltech

Exoplanet Types

So far scientists have categorized exoplanets into the following types: Gas giant, Neptunian, super-Earth, and terrestrial, with subcategories — such as mini-Neptunes — within those groups. How are they alike or different? What makes them special?

Learn More about Exoplanet Types

HD 40307 g, a super earth exoplanet is on a poster featuring a skin diver without a parachute.

Exoplanet Travel Bureau

Journey beyond our solar system with guided tours, 360-degree surface visualizations, and our popular travel posters.

How Do We Find Exoplanets?

Exoplanets are far, but scientists have discovered some creative ways to spot these elusive objects.

Want to Help Us Look?

NASA welcomes the public to assist with projects and sift through data. Collaborating with NASA scientists, volunteers known as citizen scientists have contributed to thousands of important discoveries.

Astronomers have found a clever new way to slice and dice the flickering light from a distant star in a way that reveals the strength of gravity at its surface. The new technique can also be used to significantly improve estimates of the sizes of the hundreds of exoplanets that have been discovered in the last 20 years. Current estimates have uncertainties ranging from 50 percent to 200 percent. Using the improved figures for the surface gravity of the host stars calculated by the new method should cut these uncertainties at least in half.

Strange New Worlds

Explore an interactive gallery of some of the most intriguing and exotic exoplanets discovered so far.

Target Star catalog

Other Stars, Other Habitable Worlds?

The Target Star Catalog is a guide to intriguing nearby stars that astronomers want to study with future missions, such as the Habitable Worlds Observatory, which will be built specifically to find and observe Earth-like exoplanets, to search for signs of life.

Browse the Target Star Catalog

An M dwarf star is seen with three exoplanets.

An artist's rendering of a red dwarf or M star, with three exoplanets orbiting. About 75 percent of all stars in the sky are the cooler, smaller red dwarfs.

NASA/JPL-Caltech

otherworldly Encyclopedia

Exoplanet Catalog

Learn more about every confirmed exoplanet — nearly 6,000 and counting — in this continuously updated resource. View interactive 3D models, read descriptions and vital statistics, and filter by exoplanet type, or by the method used to discover it, or by the spacecraft, observatory, or other facility that found it.

Browse the Exoplanet Catalog

Screenshot of the Eyes on Exoplanets interactive showing an orange gas giant planet KELT-4 A b.

NASA

17 Images

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K2-33b, shown in this illustration, is one of the youngest exoplanets detected to date using NASA's Kepler Space Telescope.

Artist's impression of the ten hot Jupiter exoplanets. Two rows of exoplanet illustrations. There are 5 planets of varying sizes, colors, and atmos...

Artist concept of a gas giant planet circling a pair of red dwarf stars in the system OGLE-2007-BLG-349. The pair of red dwarf stars is in the uppe...

Astronomers using data from NASA Kepler mission and ground-based telescopes recently discovered the three smallest exoplanets known to circle anoth...

This artist's rendering shows a large exoplanet causing small bodies to collide in a disk of dust.

Three possible interiors of the TRAPPIST-1 exoplanets. All seven planets have very similar densities, so they likely have a similar compositions.

This illustration shows a red dwarf star orbited by a hypothetical exoplanet. By mining data from NASA's GALEX spacecraft, a team of astronomers id...

A NASA-led team of scientists determined that WASP-18b, a 'hot Jupiter' located 325 light-years from Earth, has a stratosphere that's loaded with c...

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Get set for launch. “Eyes on Exoplanets” will fly you to any planet you wish—as long as it's far beyond our solar system. This fully rendered 3D universe is scientifically accurate, allowing you to zoom in for a close look at more than 1,000 exotic planets known to orbit distant stars.