Jupiter Ganymede: The huge moon contains water vapor in the atmosphere

Researchers detect water vapor in the atmosphere of the largest moon in the solar system. Ganymede orbits Jupiter – the probe must now investigate more closely.

STOCKHOLM – Water is a prerequisite for life as we know it – and is therefore probably the most researched chemical compound in space. But in reality, you don’t have to look deep into space to discover water – the element is also found in the solar system, researchers have discovered. Research has known for some time that there is more water on Jupiter’s moon Ganymede than all the oceans on Earth. However, on Ganymede it is cold, water freezes on its surface and the depth of the oceans is assumed to be about 160 kilometers.

But now researchers have detected water vapor around Ganymede for the first time – an important finding. “Where there is water, there can be life as we know it,” said a message from NASA. Determining liquid water on other celestial bodies is important in the search for extraterrestrial habitable planets. In fact, the water that a team led by Lorenz Roth of the Royal Technical University (KTH) in Stockholm discovered using the Hubble Space Telescope is not liquid, but gaseous. It’s a “transcendent water atmosphere” around the icy moon Ganymede – sublimated water is water that goes from its frozen state directly to a gaseous form and jumps over its liquid state.

Water vapor discovered in the atmosphere of Jupiter’s moon Ganymede

Roth’s team analyzed old images taken by Ganymede’s recently repaired Hubble Space Telescope and found discrepancies that can only be resolved in one way: by adding another molecule – water. The researchers found that although temperatures of less than 125 degrees Celsius predominate on the daytime side of the moon, the sun’s rays are sufficient to solidify the ice and form water vapor. During the day, water vapor dominates the thin atmosphere of Ganymede, which freezes again at night. “The water vapor that we measured is coming from the rising ice from warm icy regions,” Roth explains.

Water Vapor on Jupiter’s Moon Ganymede – The JUICE mission should take a closer look

Geophysicist Joachim Sauer (University of Cologne), who participated in the study as a participant, adds: “According to the current state of knowledge, it cannot be assumed that the hydrosphere is fed from the water reservoir under the surface of the ice” author. “Knowing the atmosphere of water vapor is very important, however, in order to be able to properly evaluate other observations of the moon, which also influence the ocean’s characterization,” continues Sauer. study was Published in Nature Astronomy.

After discovering water vapor in the atmosphere of Jupiter’s moon Ganymede, scientists are looking forward to the upcoming ESA mission “JUICE”. The JUICE mission is scheduled to begin in 2022 and reach Jupiter in 2029. The focus of the search is on Jupiter’s three largest moons Ganymede, Callisto and Io – with a particular focus on Ganymede, the largest moon in our solar system, which is even larger than the planet’s Mercury. Ganymede was chosen because the moon is “a natural laboratory for analyzing the nature, evolution, and habitability of ice worlds,” according to Esa. “Our results can provide the JUICE team with valuable information for better use of the space probe,” says Roth happily. NASA’s Juno mission is currently orbiting Jupiter and taking a closer look at Ganymede.

Jupiter’s moon Ganymede in focus: Water vapor discovered the atmosphere

JUICE’s mission is also to investigate Jupiter’s system of 79 moons in general. how did that happen? How were the four great moons of Galilee formed? The research aims to use Jupiter and its moons to understand how gas giant planets and their moons form and evolve. These results will also then be transmitted to Jupiter-like systems of exoplanets and help in the search for life in the universe. (Tania Banner)