Galileo Flew Within 99 Miles of Jupiter's Moon Amalthea

Galileo flew past Jupiter’s moon Amalthea on November 5, 2002, passing within about 99 miles (159 kilometers) of the small moon.

Key details

• Amalthea measures about 168 miles (270 kilometers) long.
• The moon orbits about 112,468 miles (181,000 kilometers) from Jupiter.
• A NASA announcement described Amalthea’s density as lower than that of water ice and suggested the moon may contain substantial water ice and rock despite its porosity.
• Astronomer Edward Emerson Barnard discovered Amalthea in September 1892 using the Lick Observatory telescope.

Galileo passed about 99 miles (159 kilometers) from Amalthea.

Why it matters

Amalthea is one of Jupiter’s moons, and Galileo’s close pass gave the spacecraft an opportunity to study a small body orbiting the planet. Its reported low density offers clues about the materials that may make up the moon.