NASA Juno Measures Io’s Subsurface Heat, Finds 40F Temperature Rise Within Feet

3 articles · Updated · NASA · Jul 22

Juno’s microwave radiometer made the first subsurface temperature measurements on Io, detecting temperatures rising by more than 40 degrees Fahrenheit just several feet below the surface.
Data from flybys at about 930 miles in December 2023 and February 2024 suggest either steady heat flow of 1 to 3 watts per square meter or cooling lava flows buried under 30 to 35 feet of crust.
The same observations showed broad smooth plains stretching 60 miles or more, with low-density surface material more like pumice or volcanic ash than solid rock.
NASA said the technique extends Juno’s earlier probing of icy moons Europa and Ganymede and could help scientists study tidal heating across the solar system and even subsurface temperature patterns near Earth volcanoes.

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NASA12h ago

NASA Juno Mission Measures Subsurface Temperature on Jupiter's Moon Io

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NASA's Juno Peers Beneath Io's Surface - NASA Science

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NASA's Juno just measured heat beneath Io's surface for the first time. During two close flybys, the spacecraft's microwave instrument detected temperatures rising by more than 40°F only several feet beneath the

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Juno’s 2023–2024 Io Flybys Reveal True Volcanic Power, Subsurface Structure, and Challenge Magma Ocean Models

Overview

Between December 2023 and February 2024, NASA's Juno spacecraft made a series of close flybys of Jupiter's moon Io, marking the first time scientists could look beneath its surface. These historic observations collected valuable data, offering new insights into Io's intensely volcanic interior and dynamic surface processes. The findings represent a major step forward in understanding the most volcanically active body in our solar system, as Juno's mission revealed details about Io's volcanism that were previously unknown. This progress highlights the importance of Juno's ongoing exploration and the significance of its advanced instruments.

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