A NASA spacecraft is set to swing past one of Jupiter’s moons Thursday, giving astronomers a close-up view of one of the most volcanic spots in the solar system.
The Juno probe, which has been orbiting Jupiter since July 2016, is set to conduct a flyby of Io, one of the 80 known moons in Jupiter’s system. Io’s magma-encrusted surface is pockmarked with hundreds of volcanoes, and scientists are keen to understand how these eruptions change Jupiter’s magnetosphere and what effect they may have on the planet’s vivid auroras.
Over the course of the next year and a half, the Juno spacecraft will carry out a total of nine flybys of Io. Two of the close encounters will take the probe to within 930 miles of the moon's surface.
Earlier this year, Juno captured a dramatic view of Io from a distance of around 50,000 miles. Io’s volcanically active surface, dotted with hundreds of volcanoes and marred with lakes of molten silicate lava, appeared to glow in the infrared image. The bright spots in the portrait indicate areas of higher temperature, according to NASA.
Juno launched into space in 2011 and arrived at Jupiter five years later. The spacecraft then spent another five years studying the largest planet in the solar system, peering through Jupiter’s dense clouds and studying the planet’s atmosphere and weather. The expedition was designed to help astronomers understand how Jupiter formed and evolved, and how other gas giants in the solar system came to be.
Last year, NASA extended the Juno mission through September 2025. The probe is continuing to study Jupiter, as well as the many moons in the planet’s system.
The spacecraft has already performed close flybys of two other moons: Ganymede in 2021 and Europa earlier this year.
“With each close flyby, we have been able to obtain a wealth of new information,” Scott Bolton, the associate vice president of the Southwest Research Institute in San Antonio and the principal investigator of the Juno mission, said in a statement. “Juno sensors are designed to study Jupiter, but we’ve been thrilled at how well they can perform double duty by observing Jupiter’s moons.”
During its extended mission, the Juno probe will examine Jupiter's interior structure, internal magnetic field, atmosphere and auroras. The spacecraft will also fly through clouds of charged particles surrounding Europa and Io multiple times, gathering data on the radiation levels in these regions, according to NASA. The agency said mission scientists are also hoping to devote time to studying dust in Jupiter's faint rings.