Europe: this study bodes well for the search for extraterrestrial life

A study based on radar observations in Greenland suggests that the ice shell of Jupiter’s moon Europa may contain an abundance of pockets of water below its surface. The results of this work, published in Nature Communications, obviously have implications for the search for extraterrestrial life. Two missions will soon be sent on site to find out more.

Europa is a prime candidate for the search for extraterrestrial life, along with Mars and Enceladus. And for good reason, the data suggest the presence of a salty and probably oxygen-rich underground ocean possibly in contact with its rocky core. In theory, such flirting could give rise to complex chemical reactions that could lead to the appearance and development of living beings.

Unfortunately, we know that this ocean evolves under several tens of kilometers of ice, which makes the prospect of its analysis very discouraging. However, mounting evidence suggests that the ice shell of Europa could be a site of potential habitability in its own right.

A terrestrial analogue

On Earth, researchers are analyzing the polar regions using airborne geophysical instruments to understand how the growth and retreat of ice caps could impact sea level rise.

Analyzes of data collected from 2015 to 2017 by NASA’s Operation IceBridge in Greenland revealed how a double ridge, located northwest of the territory, occurred when ice fractured around a pocket pressurized liquid water that was refreezing inside the ice cap. This process would thus have caused the elevation of these two ridges on the surface.

However, “double ridges” have also been known to appear over Europe, although they are much larger than those over Greenland. Some can indeed reach thirty meters high, separated by valleys several hundred meters wide.

Scientists have known about the existence of these features since the 1990s. However, until now, they have never been able to explain their presence. It is finally quite possible that processes comparable to those operated in Greenland took place in Europe. The water from its underground ocean could indeed have been forced up the ice shell by means of fractures, before freezing. This process would eventually cause the shell to rupture, revealing these huge double crest formations to us.

Two missions to get to the bottom of things

Rather than behaving like an inert block of ice, Europa’s shell appears to undergo a variety of geological and hydrological processes that help bring water and nutrients to the surface. Interesting chemical substances coming from space or other moons of Jupiter could “join the party” to promote, why not, the emergence of life.

This work is all the more interesting as two missions equipped with radars (ESA’s Juice and NASA’s Europa Clipper) will soon be on site. The data collected can then be compared with those of Greenland.