Confirm possibility of extraterrestrial life in the ocean of Saturn’s moon Enceladus
has discovered new evidence of a key component for life in the subterranean ocean of Saturn\’s moon Enceladus.
The search for e̳x̳t̳r̳a̳t̳e̳r̳r̳e̳s̳t̳r̳i̳a̳l̳ life has become even more interesting now that a team of scientists, including Dr. Christopher Glenn of the Southwest Research Institute, has discovered new evidence of a key component of life in the subterranean ocean of Saturn\’s moon Enceladus. . The new model suggests that Enceladus\’ ocean should be relatively rich in dissolved phosphorus, an essential ingredient for life.
“Enceladus is one of humanity\’s main targets in the search for life in the solar system,” said Glein, a leading expert in the field of e̳x̳t̳r̳a̳t̳e̳r̳r̳e̳s̳t̳r̳i̳a̳l̳ oceanography. He is co-author of a paper describing the research in the Proceedings of the National Academy of Sciences. “Since NASA\’s Cassini spacecraft visited the Saturn system, we have been repeatedly amazed at the discoveries made possible by the data collected.”
SwRI Principal Scientist Dr. Christopher Glein contributed new findings that phosphorus in the orthophosphate form (eg, HPO42-) is likely abundant in the subterranean ocean of Saturn\’s moon Enceladus. A soda or alkaline ocean (containing NaHCO3 and/or Na2CO3) within Enceladus interacts geochemically with a rocky core. Models indicate that this interaction promotes the dissolution of phosphate minerals, making orthophosphate readily available to possible life in the ocean. Because phosphorus is an essential ingredient for life, this finding strengthens the growing evidence for habitability within this small moon of Saturn.
The Cassini spacecraft discovered Enceladus\’ subsurface liquid water and analyzed samples as ice grains and water vapor erupted into space from cracks in the moon\’s icy surface.
“We learned that feathers contain the basic requirements for almost everything we know about life,” says Glenn. “While the biologically essential element phosphorus has not been directly identified, our team found evidence of its presence in the ocean beneath the lunar ice crust.
One of the most profound discoveries in planetary science in the last 25 years is that worlds with oceans below the ice surface are common in our solar system. These worlds include the icy moons of giant planets like Europa, Titan, and Enceladus, as well as more distant objects like Pluto. Worlds like Earth with surface oceans must reside within a narrow range of distances from their host stars to maintain temperatures that support surface liquid water. Inner water ocean worlds, however, can occur over a much wider range of distances, vastly expanding the number of habitable worlds likely to exist in the entire galaxy.
“The search for e̳x̳t̳r̳a̳t̳e̳r̳r̳e̳s̳t̳r̳i̳a̳l̳ habitability in the solar system has shifted focus as we now search for the building blocks of life, including organic molecules, ammonia, sulfur-containing compounds, and the chemical energy needed to support life,” Glenn said. an intriguing example because previous work has shown that it may be scarce in Enceladus\’ oceans, dimming the prospects for life.”
Phosphorus in the form of phosphates is essential for all life on Earth. It is essential for the creation of DNA and RNA, energy-carrying molecules, cell membranes, bones and teeth in humans and animals, and even marine microbial communities for plankton.
Team members ran thermodynamic and kinetic models to simulate the geochemistry of phosphorus based on Cassini\’s knowledge of the ocean floor system on Enceladus. In the course of their research, they developed the most detailed geochemical model to date of how seafloor minerals dissolve in Enceladus\’ ocean and predicted that phosphate minerals would be unusually soluble there.
“The underlying geochemistry has an elegant simplicity that makes the presence of dissolved phosphorus unavoidable, reaching levels close to or even higher than those found in seawater on modern Earth,” Glein said. “For astrobiology, this means we can be more certain than before that Enceladus\’ ocean is habitable.”
According to Glein, the next step is clear: “We have to go back to Enceladus and see if it really is inhabited.”