Science

Europa Plumes: New Evidence Found for Water on Jupiter Moon

Europa Plumes: New Evidence Found for Water on Jupiter Moon

Before ending its mission in 2003 with a planned crash into Jupiter's atmosphere, Galileo reported the first data suggesting a liquid water ocean under Europa's surface.

Old data from NASA's Galileo spacecraft shows that it may have traveled through a plume of water on the moon of Europa in 1997 without scientists realizing what had happened.

It comes from measurements made from much closer up during a flyby of Nasa's now-expired Galileo spacecraft. To study the makeup of the water on Europa, scientists would only need to perform flybys with spacecraft going through the plumes instead of landing on the moon.

NASA scientists have also proposed a mission for a spacecraft that would actually land on the Europan surface, tentatively slated for a 2024 launch.

At 1,900 miles (3,100 kilometers) wide, Europa is slightly smaller than Earth's moon. Scientists have been looking for proof of suspected water plumes emerging from Europa but haven't been able to prove it.

It is thought to have an iron core, a rocky mantle and a surface ocean of salty water, like Earth.

Europa is one of the most talked-about bodies in the Solar System, not only because it was so integral to Arthur C Clarke's classic 2001 series, and the new data is already being put into action.

"Observations of plumes may tell us a lot about whether or not Europa's ocean has the ingredients suitable for life". The particles that are spread by the plumes will be found in the atmosphere of Europa. In late 2012, Hubble spotted signs of such a feature near the moon's south pole.

That said, the new study doesn't necessarily confirm the existence of a plume, either.

If the existence of the plumes is confirmed and they are linked to Europa's ocean, they could provide a tantalisingly straightforward way to sample the moon in search of signs of life.




When plumes of water spray out of Europa, the molecules are immediately battered by highly energetic particles, a process that smashes them into charged ions. The model simulations that included plumes from Europa closely matched the Galileo data, but the model without them did not.

Galileo found Europa's magnetic field intensified and shifted orientation just as the spacecraft made its closest approach to the moon. For example, in the 2014 and 2016 candidate detections, the possible plumes blocked some ultraviolet light emitted by Jupiter.

The new data, reported in the scientific journal Nature Astronomy, was examined by a team led by the University of MI. The agency is developing a $2 billion Jupiter-orbiting mission called Europa Clipper, which is scheduled to launch in the early to mid-2020s.

Europa is objectively one of the most badass moons in the solar system.

NASA officials have also said they'd like Clipper to dive through Europa's putative plumes, if possible, to potentially grab fresh samples of the moon's ocean (if plume material is indeed coming directly from that ocean).

"It's unlikely that plumes, if they exist, come directly from a subsurface ocean layer, since the surface ice layer is thought to be kilometers thick". Ephemeral plumes could make it tough to plan sample-snagging flybys.

The results were in "satisfying agreement", Jia said.

Since Galileo's end, the Hubble Space Telescope has periodically observed the Jovian system.

Such activity may be caused by different individual jets or geysers turning on and off over time, he added.

"To detect a plume for certain, we'll have to return to the Jupiter system, and NASA's Europa Clipper spacecraft, now in development, will do just that", Cynthia Phillips, a NASA researcher told Mashable.