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Jupiter Moons

Jupiter has 53 named moons and another 26 awaiting official names. Combined, scientists now think Jupiter has 79 moons.

There are many interesting moons orbiting the planet, but the ones of most scientific interest are the first four moons discovered beyond Earth—the Galilean satellites. More ›

Critical Science Targets

Io is the most volcanically active body in the solar system.

Europa might be the best place to look for environments where life could exist.

Ganymede is the largest satellite in our solar system. It is larger than Mercury and Pluto, and three-quarters the size of Mars.

Callisto is the most heavily cratered object in our solar system.

Related News

A technique for scanning Mars rocks for microscopic fossils is also being developed to hunt for microbes on Enceladus, Titan, and Europa.

Probing for Life in the Icy Crusts of Ocean Worlds

Probing for Life in the Icy Crusts of Ocean Worlds

The spacecraft will use multiple flybys of the moon to investigate the habitability of this ocean world.

NASA's Europa Clipper Builds Hardware, Moves Toward Assembly

NASA's Europa Clipper Builds Hardware, Moves Toward Assembly

Set to launch next year, the agency’s Psyche spacecraft will explore a metal-rich asteroid in the main asteroid belt between Mars and Jupiter.

NASA Begins Final Assembly of Spacecraft Destined for Asteroid Psyche

NASA Begins Final Assembly of Spacecraft Destined for Asteroid Psyche

This image from NASA’s Juno mission captures the northern hemisphere of Jupiter around the region known as Jet N7.

Jupiter's Visible and Invisible Winds

Jupiter's Visible and Invisible Winds

A proposed mission called Io Volcano Observer (IVO) would visit Jupiter’s moon Io, which is a true volcanic wonderland.

Io Volcano Observer: Following the Heat and Hunting Clues to Planet Evolution

Io Volcano Observer: Following the Heat and Hunting Clues to Planet Evolution

The gas-giant orbiter is illuminating the provenance of Jovian polar light shows.

NASA's Juno Reveals Dark Origins of One of Jupiter's Grand Light Shows

NASA's Juno Reveals Dark Origins of One of Jupiter's Grand Light Shows

Zodiacal light is sunlight reflected toward Earth by dust orbiting the Sun. Juno scientists now think Mars may be the source of the dust.

Detections by Juno Spacecraft Shatter Ideas About Origin of Zodiacal Light

Detections by Juno Spacecraft Shatter Ideas About Origin of Zodiacal Light

Whether you're doing it for the nerd cred or the pie, this week on #10Things, we've got all the ways you can celebrate #PiDay with NASA.

10 Ways to Celebrate Pi Day with NASA on March 14

10 Ways to Celebrate Pi Day with NASA on March 14

A wayward young comet-like object orbiting among the giant planets has found a temporary parking place along the way.

Comet Makes a Pit Stop Near Jupiter's Asteroids

Comet Makes a Pit Stop Near Jupiter's Asteroids

As astronomers discovered asteroids hiding in Jupiter’s Lagrange points, they began referring to them as “Trojan asteroids.”

How Were the Trojan Asteroids Discovered and Named?

How Were the Trojan Asteroids Discovered and Named?

JPL's lucky peanuts are an unofficial tradition at big mission events.

What Are NASA's Lucky Peanuts?

What Are NASA's Lucky Peanuts?

This view of Jupiter’s turbulent atmosphere from NASA’s Juno spacecraft includes several of the planet’s southern jet streams.

Deep Jet Streams in Jupiter's Atmosphere

Deep Jet Streams in Jupiter's Atmosphere

Phobos orbits through a stream of charged atoms and molecules that flow off the atmosphere of Mars, new research shows.

Could Phobos Help Reveal Secrets of the Martian Past?

Could Phobos Help Reveal Secrets of the Martian Past?

10 Things to Expect in Planetary Science for 2021

10 Things to Expect in Planetary Science for 2021

10 Things to Expect in Planetary Science for 2021

They focus on our star, but three of NASA’s Sun-watching spacecraft have also captured unique views of the planets.

Unique Solar System Views from Sun-Watching Spacecraft

Unique Solar System Views from Sun-Watching Spacecraft

Images of Jupiter’s hot spots are key to understanding the role of storms and waves in Jupiter’s atmosphere.

A Hot Spot on Jupiter

A Hot Spot on Jupiter

The spacecraft will become an explorer of the full Jovian system – Jupiter and its rings and moons.

NASA's Juno Mission Expands Into the Future

NASA's Juno Mission Expands Into the Future

Jupiter, left, and Saturn, right, above Chapel Hill, North Carolina, during the “great conjunction.”

Saturn and Jupiter's Great Conjunction

Saturn and Jupiter's Great Conjunction

Skywatchers are in for a treat soon as Jupiter and Saturn appear to merge into what's become popularly known as the "Christmas Star."

The Great Conjunction of Jupiter and Saturn

The Great Conjunction of Jupiter and Saturn

Some of Juno's latest findings touch on "hot spots" in the planet's atmosphere.

NASA's Juno Spacecraft Updates Quarter-Century Jupiter Mystery

NASA's Juno Spacecraft Updates Quarter-Century Jupiter Mystery

Tips for photographing the sky during December's conjunction of Saturn and Jupiter

How to Photograph the Conjunction of Saturn and Jupiter

How to Photograph the Conjunction of Saturn and Jupiter

NASA’s VIPER will be the first off-world rover to have its brains split in two as it explores the Moon’s surface in search of water ice.

VIPER's Many Brains are Better than One

VIPER's Many Brains are Better than One

For Artemis astronauts traveling to the Moon, two space weather instrument suites, NASA’s HERMES and ESA’s ERSA, will provide an early forecast.

Lunar Gateway Instruments to Improve Forecasting for Artemis Astronauts

Lunar Gateway Instruments to Improve Forecasting for Artemis Astronauts

Plumes of water vapor that may be venting into space from Jupiter's moon Europa could come from within the icy crust itself, according to new research.

Potential Plumes on Europa Could Come From Water in the Crust

Potential Plumes on Europa Could Come From Water in the Crust

New experiments re-create the environment of Europa and find that the icy moon shines, even on its nightside. The effect is more than just a cool visual.

Europa Glows: Radiation Does a Bright Number on Jupiter's Moon

Europa Glows: Radiation Does a Bright Number on Jupiter's Moon