New images of Jupiter’s moon show volcanic landscape – 01/09/2024 – Science

A NASA spacecraft quickly passed by Io, one of Jupiter’s largest moons and the most volcanically active world in our Solar System. The spacecraft, the Juno orbiter, made its closest pass yet of the satellite’s turbulent landscape and sent back photos dotted with steep cliffs, sharp mountain peaks, lakes of accumulated lava and even a volcanic plume.

“I was amazed,” said Scott Bolton, a physicist at the Southwest Research Institute and principal investigator for the Juno mission. Bolton noted how Io is “incredibly colorful”—dyed in shades of orange and brown because of the presence of sulfur and flowing lava. He compared the moon to a peperoni pizza.

Studying these features could help scientists discover what drives Io’s volcanoes, some of which hurl lava tens of kilometers into space, and confirm that this activity comes from an ocean of magma hidden beneath the moon’s crust. Deciphering the secrets of volcanoes could eventually reveal the influence Jupiter has on their eruptions, which could be a clue to how the gas giant and its moons formed.

The Juno spacecraft, designed to study the origin and evolution of Jupiter, arrived at the planet in 2016. NASA extended the mission in 2021, and the space probe captured photos of the Jovian moons Ganymede, Europa and, most recently, Io.

It is not the first time that a NASA spacecraft has flown over Io. In 1979, Voyager 1 discovered that Io was volcanically active during its journey into interstellar space. Two decades later, NASA’s Galileo mission sent back what Bolton calls “postage stamps,” or close-ups of specific features on Io’s surface.

Juno has made several more distant observations of Io in recent years. Its last pass took place on December 30, when the spacecraft came within 1,500 km of the moon. The images captured during this visit were taken with an instrument called JunoCam and are in visible wavelengths. They are some of the highest-resolution views of Io’s global structure.

Mission managers shared six images of Io on the mission website, and a few people have since uploaded digitally enhanced versions that highlight features on Io’s surface.

Bolton said he was struck by the sharpness of the edges of some mountains in the images, which left him wondering how they are shaped and what it would be like to visit such a place.

“I wonder what it’s like to hike there,” he said, “or snowboard the peak.”

Mission scientists are already working on analyzing these images, looking for differences on Io’s surface to learn how often its volcanoes erupt, how bright and hot these eruptions are, and how the resulting lava flows behave. According to Bolton, the team will also compare Juno’s images with previous views of the Jovian moon to determine what has changed on Io over a variety of encounters.

And they’ll have a second set of data to work with in a month, when Juno completes another close pass through the explosive world on February 3.