Thanks to a new discovery made by NASA’s Cassini spacecraft there has been increased likelihood of one of Saturn’s moons harboring life.
The probe has discovered traces of molecular hydrogen (H2) in icy plumes spewing from fissures on the surface of Enceladus.
The discovery, indicates the Saturn’s moon’s oceans contain conditions critical to fueling life.
Hunter Waite, the program director of mass spectrometry studies at the South West Research Institute, said the implications of finding hydrogen were as he stated: “pretty amazing”.
To explore the composition of the ocean, NASA sent the spacecraft on a deep dive through plumes of icy material that spew from the moon’s south pole.
Past observations from other probes of the small moon indicated the plumes contained a mix of gases, water vapour, carbon dioxide and organic materials, but the latest mission provided the first evidence the ocean also contains hydrogen.
The program director added: “The problem early on was it [Cassini] was flying by really fast and these instruments had never been designed for this job. We realized the only way we were going to do this was to operate the instrument in a very different fashion.”
Dr Hunter stated that the hydrogen in the plumes was most likely produced by hydrothermal reactions between hot rocks and the water in the ocean: “We went through an inventory of the different ways you could create the hydrogen you saw, and that was the most obvious source.”
Practically the reaction charges the hot water with the chemicals necessary for microbial life to survive.
Known as methano-gensys, this process, happens around hydrothermal vents deep on the floor of the Earth’s oceans.
“Hydrothermal systems on Earth use hydrogen as a food source … to create methane,” was the explanation given by Dr Waite who also said the sheer volume of hydrogen found in the plumes meant there was a “plentiful supply of food” for microbes to exist.
But while Dr Waite unfortunately explained that the researchers were “very agnostic” about the prospect of life in Enceladus’ oceans: “We have so much hydrogen relative to methane that one could argue there’s no microbes around to eat it.”
Next decision that the agency has to make is either to return to the plumes of Enceladus with more precise instruments, or explore similar sub-surface oceans to the ones under the crust of the moon.
“Ultimately you want to send a submarine but it’s going to be while before we can manage that one,” he Dr. Waite said.
There is a plan that the Europa Clipper mission, which is set for a launch in the 2020s, will provide an opportunity to extend the research.
“We’ve given some thought to this in putting together the Europa Clipper payload so that we’ll go to Europa with some of the types of instruments [to conduct] investigations into presumably the plumes of Europa,” he said.
The Cassini mission will come to a dramatic end when the spacecraft crashes into the surface of Saturn later this year.