The long-running alien hunt has gained great momentum. Scientists have discovered that phosphorus, an important building block of life, is found in the ocean beneath the icy surface of Saturn’s moon Enceladus. The discovery was based on a review of data collected by NASA’s Cassini probe and was published Wednesday in the prestigious journal. Nature .

Cassini began exploring Saturn, its rings and moons in 2004, before burning up in the gas giant’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 co-authors. “We found large amounts of phosphorus in ice cloud samples emanating from the underground ocean.”

Geysers at Enceladus’ south pole eject icy particles into space through cracks in the surface, powering Saturn’s E ring, a faint ring outside the brighter main rings.

Scientists had found other minerals and organic compounds in previously discarded ice grains, but not phosphorus, an important building block for DNA and RNA, and also found in the bones and teeth of humans, animals, and even oceanic plankton.

Simply put, life as we know it would not be possible without phosphorus.

Glein said that although geochemical modeling previously found that phosphorus may also be present, and that prediction was published in a previous paper, it’s another thing to predict and confirm.

“This is the first time this important element has been detected in an ocean other than Earth,” first author Frank Postberg, a planetary scientist at the Free University of Berlin, told NASA.

To make the new discovery, the authors analyzed data collected by the Cassini space dust analyzer and confirmed the results by conducting laboratory experiments to show that Enceladus’ ocean contains bound phosphorus in various water-soluble forms.

Over the past 25 years, planetary scientists have discovered that worlds with oceans beneath the surface ice sheet are common in our solar system. These include Jupiter’s moon Europa, Saturn’s largest moon Titan, and an even more distant object, Pluto.

Planets with surface oceans such as Earth must be within a narrow range of their host stars to maintain the right temperatures for life, while the discovery of worlds with subsurface oceans increases the number of habitable bodies that can exist.

“With this finding, it is now known that Enceladus’ ocean meets the requirement that is generally considered the strictest for life,” said Glein. “The next step is clear – we need to return to Enceladus to see if there is indeed habitation in a living ocean.” Source