In 2005, during the spacecraft’s orbit around Saturn Cassini It passed something that specialists did not expect: a light mist of liquid water, spreading through space at a speed of almost 1290 kilometers per hour. This water gushed out from cracks in the crust of ice covering the young moon Enceladus. The probe was not designed to analyze water samples, but this discovery convinced scientists that it is necessary to launch missions to explore the icy moons of the solar system. At least six of these worlds—three around Jupiter, two around Saturn and one around Neptune—may host oceans of liquid water sandwiched between their host’s hot, rocky core, and the crust of ice covering the latter’s surface.
On the near horizon with tentacles Jupiter Icy Moons Explorer Juicewho left on April 14, and the investigation Europa Clipper, which will be launched in 2024, specialists hope to better understand the structure and dynamics of the frozen Jovian worlds. And perhaps these two missions disturb our view of the universe, in the same way as the discovery of the four largest moons (the three icy moons Europa, Ganymede and Callisto, and the volcanic world Io) of Jupiter by Galileo, in the seventeenthH century, has led to this notion that the Earth was ultimately not the only body with satellites, and therefore may not have been at the center of the world.
Is life hiding in the half-frozen mud of Europe, in the salty subglacial ocean of Ganymede? But perhaps they smother more in the solar system, under Titan’s rivers of methane and ethane or in brines found deep in the craters of the dwarf planets Ceres and Pluto? Less known worlds of the Jovian satellites.
The conditions in these strange oceans can seem very extreme. However… at a depth of 2.5 kilometers, the Greenland ice sheet reproduces the pressure conditions of ice sheets on a moon like Europa, and the concentration of microorganisms is similar to what is found in yogurt. Chemical reactions and geological activity provide the energy these life forms will need, in the same way that hydrothermal vents provide energy to the rough creatures at the bottom of Earth’s oceans. “Choose your favorite scenario to describe the emergence of life on Earth, it could also happen in Europa,” said Steve Vance, a researcher at the California Jet Propulsion Laboratory.
Microbial life specialist Allison Murray is interested in the possibility of life on these frozen worlds by exploring subterranean Lake Vida in Antarctica. She explains that experience gained by studying life in extreme environments with liquid water on Earth allows us to better understand the mechanisms at work elsewhere in the solar system. “We will visit worlds where we think life is possible,” says the researcher. Did life really evolve? Was life transferred there? To find out, we have to hold our breath and dive deeper into these worlds.
