Enceladus could be home to alien life.
In a major scientific breakthrough, phosphorus, an elemental component pivotal for life, was found abundant in the icy grains of Enceladus, one of Saturn’s small moons, based on the data collected by NASA’s Cassini mission.
The discovery of phosphorus – a life-essential element – encapsulated in the icy grains expelled from Enceladus has been made by an international research team analyzing data collected by NASA’s Cassini.
Enceladus, a small moon with a known subsurface ocean, routinely expels water through fissures in its icy crust, forming a plume at its south pole. This plume is a significant source of icy particles for Saturn’s E ring.
Saturn’s E Ring: A Cosmic Repository
From 2004 to 2017, Cassini explored the plume and E ring multiple times while on its mission. During these expeditions, the spacecraft discovered the ice grains of Enceladus to be rich in minerals and organic compounds essential for life, including the precursors to amino acids.
Until now, despite being a crucial building block for DNA and other biological functions, phosphorus had eluded detection. The element is integral for genetic information transfer, bone structure in mammals, cellular membranes, and even the energy-carrying molecules in all life forms.
Frank Postberg, a planetary scientist from Freie Universität Berlin, Germany, who spearheaded the study, confirmed on June 14, the discovery of substantial quantities of phosphorus salts in the icy grains ejected by Enceladus’ plume, the first time such a discovery has been made outside Earth.
Favorable Conditions for Life: Enceladus
Earlier studies of Enceladus’ ice grains exhibited significant amounts of sodium, potassium, chlorine, and carbonate compounds. The moon’s subsurface ocean, suggested by computer models to be moderately alkaline, appears to provide conditions suitable for life.
The researchers utilized NASA’s Planetary Data System, an archival storehouse of digital data products from NASA’s planetary missions, for their study. They paid particular attention to data captured by Cassini’s Cosmic Dust Analyzer instrument, revealing high concentrations of sodium phosphates within the ice particles.
A Step Forward in Astrobiology
Laboratory experiments by co-authors in Europe and Japan confirmed that Enceladus’ ocean contains phosphorus in 100 times the concentrations found in Earth’s oceans. They also found similar abundance of phosphate in other icy ocean worlds in the outer solar system.
Christopher Glein, a planetary scientist at the Southwest Research Institute, emphasized the discovery’s significance in astrobiology, despite the absence of proof for life on Enceladus or anywhere beyond Earth.
Even though Cassini’s mission ended in 2017, its collected data continues to be invaluable. Initially aiming to explore Saturn, its rings, and moons, the mission ended up impacting more than just planetary science.
Linda Spilker, Cassini’s project scientist at NASA’s Jet Propulsion Laboratory, emphasized the importance of the phosphorus discovery and the potential it brings for habitability in icy ocean worlds throughout the solar system.