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

For the first time, astronomers have uncovered evidence of water vapor in the atmosphere of Jupiter’s moon Ganymede. This water vapor forms when ice from the moon’s surface sublimates—that is, turns from solid to gas.

 

Scientists used new and archival datasets from NASA’s Hubble Space Telescope to make the discovery, published in the journal Nature Astronomy. Previous research has offered circumstantial evidence that Ganymede, the largest moon in the solar system, contains more water than all of Earth’s oceans. However, temperatures there are so cold that water on the surface is frozen solid. Ganymede’s ocean would reside roughly 100 miles below the crust; therefore, the water vapor would not represent the evaporation of this ocean. Astronomers re-examined Hubble observations from the last two decades to find this evidence of water vapor.

 

Read the full article at: esahubble.org