The long search for extraterrestrial life has just gained a major boost. The scientific community has discovered the presence of phosphorus, an element essential to life, in the ocean beneath the icy surface of a Saturn moon, Enceladus.
The discovery, based on data collected by NASA’s Cassini probe, was published this Wednesday in the journal Nature. According to AFP, the probe began exploring Saturn, its rings and moons in 2004 before burning up in the gas giant planet’s atmosphere when its mission ended in 2017.
“This is a stunning discovery for astrobiology,” said Christopher Glein of the Southwest Research Institute, one of the paper’s coauthors, confirming that “abundant phosphorus was found in samples of ice plumes coming out of the subsurface ocean”.
Geysers at the south pole of Enceladus launch ice particles – through cracks in the surface – into space, feeding one of Saturn’s rings.
Scientists had already found other minerals and organic components in the released ice grains, but not phosphorus, which is a key element for the formation of DNA and RNA, also found in the bones and teeth of people, animals and even ocean plankton. Basically, without phosphorus, life as we know it would not be possible.
Although geochemical modelling has previously indicated the possible existence of this element, scientists had not yet been able to confirm the theory, Glein explained.
“This is the first time that this essential element has been discovered in an ocean beyond Earth,” the lead author of the research, Frank Postberg, a planetary scientist at Freie Universitat Berlin, noted in a NASA statement.
Over the past 25 years, planetary scientists have discovered that celestial bodies with oceans under a surface layer of ice are common in our solar system. This includes Jupiter’s moon Europa, Saturn’s largest moon Titan, but even the most distant body Pluto.
“With this discovery, it is now known that Enceladus’ ocean satisfies what is generally considered the most important requirement for life,” Glein said. “The next step is clear – we need to go back to Enceladus to see if the habitable ocean is actually… inhabited.”
