Jupiter’s Volcanic Moon Io

During its close flyby of Jupiter’s moon Io on December 30, 2023, NASA’s Juno spacecraft captured some of the most detailed imagery ever of Io’s volcanic surface. In this image, taken by the JunoCam instrument from about 930 miles (1,500 kilometers) above the moon, Io’s night side [left lobe] is illuminated by “Jupitershine,” which is sunlight reflected from the planet’s surface.

This image is the NASA Science Image of the Month for October 2025. Each month, NASA’s Science Mission Directorate chooses an image to feature, offering desktop wallpaper downloads, as well as links to related topics, activities, and games.

Text credit: NASA/JPL–Caltech/Southwest Research Institute (SwRI)/Malin Space Science Systems (MSSS)
Image credit: NASA/JPL–Caltech/Southwest Research Institute (SwRI)/Malin Space Science Systems (MSSS); Image processing: Emma Wälimäki © CC BY