Juno Measures Subsurface Temperature on Io
NASA's Juno spacecraft has returned the first direct measurements of the temperature beneath the surface of Jupiter's moon Io. The data were gathered during two close flybys that brought the probe within a few thousand kilometres of the icy‑rocky world.
According to the measurements, the shallow subsurface of Io exhibits significant heating, consistent with the moon's status as the most volcanically active body in the Solar System. This internal warmth is thought to drive the extensive plume eruptions and lava flows observed on its surface.
The findings provide scientists with a new window into the interior processes that power Io's relentless volcanic activity. By comparing the subsurface temperature with surface observations, researchers can better understand how tidal forces from Jupiter generate heat within the moon.
While the primary focus of the flybys was to probe the deep interior, the temperature readings also complement ongoing studies of Io's atmospheric composition and surface morphology. The results are expected to inform future missions aimed at exploring the Jovian system.
NASA's Juno mission continues to operate in an extended phase, delivering valuable data not only about Jupiter's atmosphere and magnetic field but also about its largest moons.