A recent study conducted by a team of scientists from various institutions in the U.S. has shed light on the mystery of the oxygen-rich atmosphere on Callisto, one of Jupiter’s moons. Callisto, the second largest moon of Jupiter, has gained attention due to its high levels of oxygen, which has remained unexplained until now.
Previous research has suggested the possibility of an ocean beneath Callisto’s thick crust, but its composition has not been definitively determined. Additionally, it has been known that Callisto’s atmosphere contains a significant amount of oxygen, but the source of this oxygen and its persistence has remained a puzzle.
One prevailing theory suggests that Jupiter’s powerful magnetosphere may be causing the release of hydrogen, water, and oxygen molecules from the ice on Callisto’s surface. To test this theory, the scientists simulated the thermal and energetic components of Jupiter’s magnetosphere, focusing on its plasma, and estimated the energy that would reach Callisto’s atmosphere and surface.
After calculating the expected amount of oxygen release based on their simulations, the researchers compared it with the actual amount of oxygen present in Callisto’s atmosphere. The results revealed a significant discrepancy—there was a much higher concentration of oxygen than what could be explained solely by the influence of Jupiter’s magnetosphere. The difference was magnitudes greater than predicted.
Therefore, the origin of the oxygen on Callisto remains a mystery. The research team suggests that upcoming missions such as the European Space Agency’s JUICE and NASA’s Europa Clipper may provide further insights into this enigmatic phenomenon.
Overall, the study emphasizes the need for continued exploration and investigation to unravel the mysteries surrounding Jupiter’s magnetosphere and the peculiar characteristics of its moons.
Sumber:
– Shane R. Carberry Mogan et al, Callisto’s Atmosphere: The Oxygen Enigma, Journal of Geophysical Research: Planets (2023). DOI: 10.1029/2023JE007894
– Jupiter’s magnetosphere knocking molecules from ice on surface of Callisto does not explain the amount of atmospheric oxygen (Phys.org)