Europa, Jupiter’s frozen moon, might have an ocean of liquid water teeming with life. According to a new model created by N.AS.A. scientists, that ocean could indeed support life.
Recently, it was found that N.A.S.A’s space mission Galileo may have gathered proof that Europa occasionally discharges water into space, raising the possibility that water from that ocean occasionally erupts into space.
Could Jupiter’s icy moon Europa have an underground ocean teeming with life? A new model from N.A.S.A scientists suggests that, yes, that ocean would be able to sustain life.
Water from that ocean may sometimes erupt into space; a few weeks ago it was discovered that N.A.S.A’s space probe Galileo may have collected evidence that Europa occasionally releases water into space.
This new study from researchers at N.A.S.A’s Jet Propulsion Laboratory in California also works with data from that Galileo mission, this time to model the oceans under Europa’s ice.
It’s now thought that the ocean could have been formed by breakdown of water-containing minerals due to either tidal forces or radioactive decay—evidence of the moon being geologically active.
We do know that Europa are slightly deformed by tides as its orbits Jupiter, so could be geologically active.
Presented for the first time at the virtual Goldschmidt geochemistry and conference, this not yet peer-reviewed study may have implications for other moons in the Solar System—such as nearby Ganymede, and both Enceladus and Titan around Saturn.
Facts about Europa
- Europa is the fourth largest of Jupiter’s 79 moons.
- It’s one of the largest moons in the solar system.
- With a diameter of 3,100 km, Europa is slightly smaller than the Earth’s Moon.
- Europa’s surface is made of water ice and so it reflects 5.5 times the sunlight than our Moon does.
- Europa has an ocean of liquid water beneath an 11 mile/18 kilometer thick shell of ice. It also has a rocky seafloor.
- It’s been photographed by N.A.S.A’s Voyager and Galileo spacecraft.
- Galileo is credited with discovering Europa, along with Ganymede, Io and Callisto, on January 8, 1610.
- As Europa orbits Jupiter around 780 million km from the Sun, the surface temperature never rises above -160º Celsius; the ocean’s temperature is unknown.
- Scientists have long believed that its surface crust of ice floats on a subsurface ocean, but that ocean’s composition and origins are unclear.
What materials make up Europa’s ocean?The makeup of Europa’s huge ocean will determine whether it can support life. Scientists can only glance at the moon’s frozen surface because they haven’t sampled it and don’t know anything about it.
Geologically speaking, Europa is youthful and dynamic, with ridges, fissures, and cracks covering its frozen surface. There are several “chaos” areas, and it is always changing. It appears to be dominated by three chemical terrains, according to Galileo data:
The final one is intriguing. It is in a “chaos” area where there may be openings where ocean water can enter or where the ice may have melted.
The only thing the scientists are aware of is that it appears smooth in Galileo’s infrared photographs, which is what sodium chloride appears to look like when scientists mimic Europa’s surface conditions in a lab.
So they used the Hubble Space Telescope to search four times in optical (visible) wavelengths of light for the distinctive colors of sodium chloride. Multiple times, and only in “chaotic” areas of Europe, they were discovered.
Jupiter’s large moon, Europa, is covered by a thick crust of ice above a vast ocean of liquid water.
Why is this crucial?In the publication, it is stated that “The presence of sodium chloride on Europa has profound implications for our knowledge of the interior chemistry and its geochemical development through time.” It implies that the circulation of hot water, such that found in Earth’s seas, might result in an ocean that is abundant in sodium chloride.
According to senior researcher Mohit Melwani Daswani, “it was thought that this ocean may still be rather sulfuric, but our models, along with data from the Hubble Space Telescope revealing chloride on Europa’s surface, suggests that the water most likely became chloride-rich.”
In other words, its makeup started to resemble Earth’s oceans more. We think that there is a good chance that life could exist in this water.
What questions remain?
“A long-standing question over whether a “cloaked ocean” world like Europa could be habitable boils down to whether it can sustain a flow of electrons which might provide the energy to power life,” said Professor Steve Mojzsis, Professor of Geology at the University of Colorado, and not connected with the research. “What remains unclear is whether such icy moons could ever generate enough heat to melt rock; certainly interesting chemistry takes place within these bodies, but what reliable flow of electrons could be used by alien life to power itself in the cold, dark depths?”
“A key aspect that makes a world “habitable” is an intrinsic ability to maintain these chemical disequilibria. Arguably, icy moons lack this ability, so this needs to be tested on any future mission to Europa.”
However, the presence of sodium chloride isn’t proven. “Regardless of whether the observed sodium chloride directly relates to the ocean composition, its presence warrants a re-evaluation of our understanding of the geochemistry of Europa,” reads the paper.
An artist’s concept inspired by recent discoveries on Europa of regions that look very much like … [+]
GETTYIs Europa our best chance of finding life in our solar system?
It’s one of them. “Europa is one of our best chances of finding life in our solar system. N.A.S.A’s Europa Clipper mission will launch in the next few years, and so our work aims to prepare for the mission, which will investigate Europa’s habitability,” said Melwani Daswani.
“Our models lead us to think that the oceans in other moons, such as Europa’s neighbor Ganymede, and Saturn’s moon Titan, may also have formed by similar processes. We still need to understand several points though, such as how fluids migrate through Europa’s rocky interior.”
The Europa Clipper mission
Scheduled to launch in 2023, N.A.S.A’s Europa Clipper mission will perform about 45 flybys, in each pass photographing the moon’s icy surface in high resolution.
It will find out for sure if the conditions are right for life on the icy moon.
The Jupiter Icy Moons Explorer (JUICE) mission
Set to launch in June 2022 and reach Jupiter in 2029, the European Space Agency’s JUpiter ICy moons Explorer (JUICE) will spend three and a half years examining Europa and two of Jupiter’s other large moons, Ganymede and Callisto. Its cameras and ice-penetrating radar will be used to study the composition of Europa’s icy crust, detecting whether there are reservoirs of water between layers of ice.
Soucre: forbes.com
