Sodium, not heat, reveals volcanic activity on Jupiter's moon Io
January 31, 2019, Planetary Science Institute
A large volcanic event was detected on Jupiter's moon Io using Jovian sodium nebula brightness variation, a new paper in Astrophysical Journal Letters said.
"These results highlight the growing body of evidence that the traditional way of monitoring Io's volcanism – by looking for temperature changes on its surface caused by hot lava – is not able to reliably find these large gas release events," said Jeff Morgenthaler, a senior scientist at the Planetary Science Institute and lead author on the paper "Large Volcanic Event on Io Inferred from Jovian Sodium Nebula Brightening."
"Lack of a strong infrared counterpart to this event tells us something about the geology of Io. To use some well-known Earth analogies, this volcanic event may have been from an eruption more like that of Mount St. Helens in 1980, which released lots of gas and dust, rather than Kilauea's recent eruptions in Hawaii, which produce lots of hot lava," Morgenthaler said.
"The volcanic event occurred sometime between mid-December 2017 and early January 2018. Gas from the event filled Jupiter's magnetosphere, the region of space dominated by Jupiter's magnetic field, with excess material until early June," Morgenthaler said. "Io is the most volcanic body in the solar system, so its volcanism is the ultimate source of the material. Interestingly, this event, which was the longest recorded by this technique, was not independently reported by any other Io volcanic monitoring technique, despite significant number of observations in support of NASA's Juno mission."
Read more at: https://phys.org/news/2019-01-sodium-reveals-volcanic-jupiter-moon.html#jCp