Using archival data from the Cassini orbiter, scientists have now detected the first evidence of phosphorus – a key element in the development of life on Earth – coming from the interior of the Saturn moon Enceladus.
The small moon is known to possess a subsurface ocean, and water from that ocean erupts through cracks in Enceladusโ icy crust as geysers at its south pole, creating a plume. The plume then feeds Saturnโs E ring (a faint ring outside of the brighter main rings) with icy particles.
During its mission at the gas giant from 2004 to 2017, Cassini flew through the plume and E ring numerous times. Scientists found that Enceladusโ ice grains contain a rich array of minerals and organic compounds โ including the ingredients for amino acids โ associated with life as we know it.
Phosphorus, the least abundant of the essential elements necessary for biological processes, hadnโt been detected until now. The element is a building block for DNA, which forms chromosomes and carries genetic information, and is present in the bones of mammals, cell membranes, and ocean-dwelling plankton. Phosphorus is also a fundamental part of energy-carrying molecules present in all life on Earth. Life wouldnโt be possible without it.
โWe previously found that Enceladusโ ocean is rich in a variety of organic compounds,โ said Frank Postberg, a planetary scientist at Freie Universitรคt Berlin, Germany, who led the new study, published on Wednesday, June 14, in the journal Nature. โBut now, this new result reveals the clear chemical signature of substantial amounts of phosphorus salts inside icy particles ejected into space by the small moonโs plume. Itโs the first time this essential element has been discovered in an ocean beyond Earth.โ
You can read the paper here. It is very important to emphasize that though phosphorus is essential for life, life in the underground ocean of Enceladus has not been discovered. The scientists have merely found evidence of this specific ingredient needed for life, suggesting that these ingredients are common in our solar system. Going from a list of ingredients to a finished dish one can eat is something else entirely.