The six elements involved: carbon, hydrogen, nitrogen, oxygen, sulfur and phosphorous. Only phosphorus was missing so far. The new analysis found some, in one of Saturn’s rings, where icy rock particles come from “ice jets” or “ice columns” from Enceladus. Analysis of data collected by the US-European Cassini probe – which orbited Saturn from 2004 to 2017 – is Posted on Wednesday in review nature.
Less well-known than Titan, the largest of Saturn’s moons, Enceladus is still at first glance more suitable for life: it is surrounded by a thick layer of ice – under which liquid water can hide. Titan sure did Atmosphere Of great size, but not suitable for life.
Jupiter’s moon, called Europa, has also been known for three decades to be covered in a thick layer of ice, beneath which are several clues indicating a sea of liquid water. A similar environment has since also been observed on two other moons of Jupiter, Ganymede and Callisto. It is suspected that Pluto could also harbor liquid water, again “squeezed” between the rocky crust and the ice cap.
What excites astrobiologists this timeis that while we have discovered some of these six elements in these other frozen worlds, this is the first timeWith Enceladus, we’ve found all six components, phosphorous being the missing ingredient so far. The researchers describe the concentration of phosphorus as higher than in Earth’s oceans: Geochemical interactions between water and rock, can explain this result. But the small number of particles analyzed by Cassini Also requires caution.
Jupiter and Saturn are so far from the Sun that the temperature of their moons allows liquid water to appear (between 0 and 100 degrees Celsius). But it is the enormous force of attraction of these planets that creates a tidal effect on their satellites, which is enough – supposedly – to heat the surface and melt the lower layer of ice.
Obviously, we have never seen these oceans – we are talking about layers of ice, the thickness of which can reach tens of kilometers. But several clues point in this direction: Cracks on Europa’s ice, which space probes have imaged since the 1970s, are typical of what one would expect from an ice sheet that is not moving, but it moves because it lies on the ocean. And the ice plumes emitted at irregular intervals from Enceladus just as they do on Europa will be the result of interactions between these tectonic forces that break up the ice and allow the occasional geyser to escape.
