How Io Became The Most Volcanic Body In Our Solar System

Scientists with NASA’s Juno mission to Jupiter have discovered that the volcanoes on Jupiter’s moon Io are each likely powered by their own chamber of roiling hot magma rather than an ocean of magma. The finding solves a 44-year-old mystery about the subsurface origins of the moon’s most demonstrative geologic features.

A paper on the source of Io’s volcanism was published on Thursday, Dec. 12, in the journal Nature, and the findings, as well as other Io science results, were discussed during a media briefing in Washington at the American Geophysical Union’s annual meeting, the country’s largest gathering of Earth and space scientists.

About the size of Earth’s Moon, Io is known as the most volcanically active body in our solar system. The moon is home to an estimated 400 volcanoes, which blast lava and plumes in seemingly continuous eruptions that contribute to the coating on its surface.

Although the moon was discovered by Galileo Galilei on Jan. 8, 1610, volcanic activity there wasn’t discovered until 1979, when imaging scientist Linda Morabito of NASA’s Jet Propulsion Laboratory in Southern California first identified a volcanic plume in an image from the agency’s Voyager 1 spacecraft.

This five-frame sequence shows a giant plume erupting from Io’s Tvashtar volcano, extending 200 miles (330 kilometers) above the fiery moon’s surface. It was captured over an eight-minute period by NASA’s New Horizons mission as the spacecraft flew by Jupiter in 2007. Credit: NASA/Johns Hopkins APL/SwRI

Io’s tidal response precludes a shallow magma ocean

Astrobiology