An artist’s rendering depicts the atmosphere on Io, Jupiter’s volcanic moon, as it collapses during daily eclipses. Image Courtesy of Southwest Research Institute
A Southwest Research Institute-led team has documented atmospheric changes on Io, Jupiter’s volcanically active satellite, as the giant planet casts its shadow over the moon’s surface during daily eclipses.
A study led by SwRI’s Constantine Tsang concluded that Io’s thin atmosphere, which consists primarily of sulfur dioxide (SO2) gas emitted from volcanoes, collapses as the SO2 freezes onto the surface as ice when Io is shaded by Jupiter. When the moon moves out of eclipse and ice warms, the atmosphere reforms through sublimation, where ice converts directly to gas.
“This research is the first time scientists have observed this phenomenon directly, improving our understanding of this geologically active moon,” said Tsang, a senior research scientist in SwRI’s Space Science and Engineering Division.
The findings were published in a study titled “The Collapse of Io’s Primary Atmosphere in Jupiter Eclipse” in the Journal of Geophysical Research. The team used the eight-meter Gemini North telescope in Hawaii and the Texas Echelon Cross Echelle Spectrograph (TEXES) for this research.
Data showed that Io’s atmosphere begins to “deflate” when the temperatures ...