What Jupiter's Satellite Europa's 'Inverted Snow' Reveals About Other Life in Space

What Jupiter’s Satellite Europa’s ‘Inverted Snow’ Reveals About Other Life in Space

Share it

A group of researchers has analyzed a curious phenomenon that probably occurs in the ocean that covers Europa, one of the satellites that orbits Jupiter: Nine ascendant. This form of ice, instead of forming in the clouds and falling to the ground due to the effect of gravity, forms in the ocean to rise to its most superficial layers (also due to the effect of gravity).

From the Arctic to Europe.
Europa is one of the many moons orbiting Jupiter and is also one of the ocean worlds in our Solar System. It is a rocky object like our Earth that, similar to our planet, is surrounded by an ocean. The differences with our planet come from its size (it is closer to that of the Moon) and from the fact that this ocean covers the entire satellite and is in turn covered with a layer of ice several kilometers thick.

For his analysis of Europe, published as an article in the journal Astrobiology, the research team took the Arctic as a reference. Studies on the Jovian satellite estimated that the temperature, pressure and salinity of its ocean in the areas closest to the ice sheet could be similar to those found in the Arctic Ocean under the ice sheet.

Freezing ice and frazil.
From there they consider two ways in which ice can form on Europa, similar to those that occur in the Arctic (excluding atmospheric precipitation). The first is ice freezing, which occurs when water freezes in the boundary zone between the ocean and the ice cap that covers it.

The second form of freezing is what they call ice. frazil (frazil ice). Ice forms in areas with a low temperature gradient, that is, areas where the temperature does not vary much; but where irregularities are formed in the contour of the ice under the surface, by the appearance of gaps in the ice, for example.

In these areas the water crystallizes forming small flakes of ice. frazil. Less dense than the surrounding water, they rise to the surface as inverted snowflakes until they become trapped in the ice cap that covers the Jovian moon.

Salt water, fresh ice.
The key is in the amount of salt that the water retains when it freezes. Both freezing ice and frazil they are less saline than the water from which they arise. But frazil it is noticeably less saline. While the former can retain a tenth of the salt in the water, the frazil could contain as little as 0.1% of this salinity. It is, in this sense, about 100 times purer.

Life in Europe.
The salinity of this moon’s oceans is key in determining its potential to harbor life and, above all, in our ability to search for it.

“When we explore Europa we are interested in the salinity and composition of the ocean, because that is one of the things that will govern its potential habitability or even the type of life that can exist. [existir] there”, explains Natalie Wolfenbarger, main author of the study.

Explore Europe on-site.
And Europe is in turn a key place in the search for extraterrestrial life in our space neighborhood. The moon is covered by an ocean whose depth ranges between 60 and 150 kilometers, in turn covered by a layer of ice between 15 and 25 kilometers thick.

Europa intrigues astrobiologists and to study it there is already a mission planned by NASA: Europa Clipper. It will depart, as scheduled, in October 2024. The mission will leave a probe orbiting Jupiter to study the satellite by getting as close as possible by flying over it on their respective orbital paths.

Europa is one of the main candidates to host life, and it is that it has, explains NASA itself, three key ingredients for life: water, even more than our Earth; Chemistry, elements such as carbon, hydrogen, nitrogen or oxygen; and energy, since despite being far from the Sun, Europa receives additional radiation because it is close to Jupiter.

The ocean worlds of our solar system.
This work may pave the way, believes Steve Vance, a scientist at NASA’s Jet Propulsion Laboratory (JPL), who was not involved in the study: “This paper is opening up a whole new set of possibilities for thinking about ocean worlds and how they work.” . It sets the stage for how we might prepare for the Europa Clipper analysis of the ice.”

Europa is not the only oceanic world in our Solar System. The exploration of these worlds has become a goal for NASA due to its great potential to harbor life. The US space agency is in the process of designing vehicles that can go beyond orbital probes like Europa Clipper and make contact with these worlds.

Many of these designs call for autonomous submarines to traverse the ice sheet to navigate the depths of these ice-trapped oceans. They can be called science fiction for now, but maybe for a short time.

Image | POT

#Jupiters #Satellite #Europas #Inverted #Snow #Reveals #Life #Space

Share it