Io orbits Jupiter at a distance of 421,700 km (262,000 mi) from Jupiter's center and 350,000 km (217,000 mi) from its cloudtops. It is the innermost of the Galilean satellites of Jupiter, its orbit lying between those of Thebe and Europa. Including Jupiter's inner satellites, Io is the fifth moon out from Jupiter.

Jupiter is the largest planet in the solar system and has, as of 2023, 95 known moons. The four largest moons of Jupiter—Io, Callisto, Ganymede, and Europa—were the first objects in the solar system discovered with a telescope. Galileo discovered them in 1610, and they are now called the Galilean satellites.

Feb 4, 2025 · Io is Jupiter's third-largest moon, spanning roughly 2,300 miles (3,700 kilometers) across, which makes it slightly bigger than Earth's moon. It orbits Jupiter at a distance of around 262,000 ...

Io is the fifth moon of Jupiter and the fourth largest moon in the solar system. It is the innermost of the Galilean moons that orbit Jupiter. Io is the most volcanically active body in the solar system, spewing out sulphur as high as 300 km (190 miles) in the air.

Io is the innermost of Jupiter’s four largest moons, which are also known as the Galilean moons (Europa, Ganymede, and Callisto are the remaining three). Because it’s the closest moon to its massive host planet, Io feels a strong gravitational pull as it orbits Jupiter. Io is also tugged on by its neighboring moons as they pass one another ...

Jan 29, 2025 · Jupiter has 95 moons that have been officially recognized by the International Astronomical Union. But the number doesn't capture the complexity of the Jovian system of moons, rings and asteroids. The giant planet has thousands of small objects in its orbit.

Jun 10, 2024 · Since 1979, when Jupiter's moon lo was found to be covered in volcanoes, astronomers and volcanologists have been fascinated by what this reddish satellite could reveal about the evolution of the Jovian system and Earth's early volcanic history.

Jan 28, 2025 · The source of Io’s torment: Jupiter. About the size of Earth’s Moon, Io is extremely close to the mammoth gas giant, and its elliptical orbit whips it around Jupiter once every 42.5 hours. As the distance varies, so does the planet’s gravitational pull, which leads to the moon being relentlessly squeezed.

Jan 29, 2025 · Modern astronomer Scott S. Sheppard has discovered the most moons of Jupiter, including nine in 2017 alone. Galileo Galilei spotted the first Jupiter moons in 1610 with a new invention called a telescope.

May 30, 2024 · The Jovian moon Io captured on Jan. 10, 2024, by the SHARK-VIS camera on the Large Binocular Telescope in Arizona. This is the highest resolution image of Io ever obtained by an Earth-based telescope. ... Berkeley professor emerita Imke de Pater was part of a team that interpreted new images of Jupiter’s moon Io taken by the Large Binocular ...