Hubble Finds Evidence of Water Vapor at Jupiter’s Moon Ganymede

  • Released Monday, July 26, 2021

Astronomers have used new and archival datasets from NASA’s Hubble Space Telescope to uncover evidence of water vapor in the atmosphere of Jupiter’s moon Ganymede.

The vapor is present due to the thermal excitation of water molecules from the moon’s icy surface.

Previous research has offered circumstantial evidence for the moon containing more water than all of Earth's oceans. However, temperatures there are so cold that water on the surface freezes and the ocean lies roughly 100 miles below the crust.

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Credit: NASA's Goddard Space Flight Center
Paul Morris: Lead Producer
Andrea Gianopoulos: Science Writer
Tracy Vogel: Science Writer

Additional Credits:
Artist’s Impression of Ganymede: Credit: ESA/Hubble, M. Garlick

Artist’s Impression of a Sublimated Water Atmosphere on Ganymede: Credit: ESA/Hubble, J. daSilva

NASA’s Juno Spacecraft Observation of Ganymede in June 2021

Video Artist’s Impression of Ganymede: Credit: ESA/Hubble, M. Garlick

Ganymede Spinning Globe: Credit: USGS Astrogeology Science Center

Music Credits:
"Mysterious Discoveries" by Bertrand Allagnat [SACEM] via Koka Media [SACEM], Universal Production Music France [SACEM], and Universal Production Music.

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Release date

This page was originally published on Monday, July 26, 2021.
This page was last updated on Wednesday, May 3, 2023 at 1:44 PM EDT.


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