Scientists Discover Water Vapor in Atmosphere of a Jupiter Moon, Look to Habitability

Astronomers have recently discovered evidence of water vapor in the atmosphere of Jupiter's moon, Ganymede, which leads scientists to believe this evidence could provide new insights into the potential habitability of "Jupiter-like exoplanetary systems," NASA said in a press release.

Ganymede, the largest moon in the solar system, has been under the Hubble Space Telescope's observation since the 1990s. The use of the archived data as well as new data published in the journal, Nature Astronomy, helped scientists examine the presence of water vapor over the last two decades.

According to NASA, the moon contains more water than all of Earth's oceans combined. However, temperatures there are so cold that any water on the surface is frozen solid, and scientists determined that due to freezing temperatures, the water vapor could not come from the evaporation of any underground oceans.

Lorenz Roth of the KTH Royal Institute of Technology in Stockholm, Sweden, led the team that analyzed Ganymede's atomic oxygen.

"So far, only the molecular oxygen had been observed," Roth said. "This is produced when charged particles erode the ice surface. The water vapor that we measured now originates from ice sublimation caused by the thermal escape of water vapor from warm icy regions."

Ganymede’s ocean would reside roughly 100 miles below the crust; therefore, the water vapor would not represent the evaporation of this ocean. Astronomers turned to ultraviolet Hubble observations for answers. (3/7)

— Hubble Space Telescope (@HubbleTelescope) July 26, 2021

While the evidence does not solidify any information about the moon's potential for life, it does provide scientists with insight into the moon's atmosphere, history and other gas giant planets' evolutions.

The discovery also gives additional information to a planned mission known as JUICE, which stands for "JUpiter ICy moons Explorer." The mission is planned by the European Space Agency (ESA) and plans to launch in 2022.

"Our results can provide the JUICE instrument teams with valuable information that may be used to refine their observation plans to optimize the use of the spacecraft," said Roth.

According to NASA, the JUICE mission will arrive on Jupiter around 2029, where it will spend at least three years making observations of Jupiter and three of its largest moons. The mission plans to focus on Ganymede as a planetary body and potential habitat.

NASA's Juno mission, which has been studying Jupiter and its environment, known as the Jovian system, since 2016, will use the information about Ganymede in continuing their studies.

In June, Juno flew closer to Ganymede than any other spacecraft in generations and recorded flyby photos that mystified scientists.

Juno Principal Investigator Scott Bolton said in a press release that it was the closest any spacecraft has come "to this mammoth moon," and added, "We are going to take our time before we draw any scientific conclusions, but until then we can simply marvel at this celestial wonder."

Newsweek reached out to NASA for comment but did not hear back in time for publication.

Ganymede, Moon of Jupiter
Scientists have recently discovered evidence of water vapor in the atmosphere of Jupiter's largest moon, Ganymede. This image of Ganymede was taken by Voyager 2. Corbis via Getty Images