Single Ice Crystal May Reveal Life on Alien Worlds
Scientists have long suspected that the icy moons within our Solar System harbor liquid oceans beneath their crusts.
Plans are underway to employ drilling robots to access these oceans, but recent research suggests that something far simpler could provide clues about the possibility of life in these environments all that's needed is a single ice particle.
The underground oceans of Europa and Enceladus, moons orbiting Jupiter and Saturn respectively, occasionally eject some material into space, where it freezes into ice crystals. Laboratory studies indicate that these oceanic realms could host life, which can be detected with the current technology in minimal quantities, as reported by the educational website IFL Science.
“For the first time, we have demonstrated that even a tiny fraction of cellular material can be identified with a mass spectrometer on board a spacecraft,” remarked the study's lead author, Dr. Fabian Klenner, a researcher at the University of Washington, in a statement.
“Our findings boost our confidence that with the next generation of instruments, we will be capable of detecting life forms similar to those on Earth, which we increasingly suspect may be present on moons harboring oceans.”
The research team chose a simple bacterium to simulate potential life forms in Europa's ocean. The chosen bacterium, Sphingopyxis alaskensis, found in the waters of Alaska, is well-suited to cold environments and can survive with minimal nutrients.
The team theorizes that bacteria could reach the surface of the buried ocean and then bubble out where cracks connect the surface with the ocean below. These bubbles could transport biomass (similar to ocean foam on sea spray), trapping these molecules within the ice particles.
Instruments aboard NASA’s Europa Clipper spacecraft, set to launch in October, are capable of detecting such materials, especially lipids. These fat molecules could form the membranes of alien life forms and are much more stable structurally than DNA.
“With the right instruments, such as the SUrface Dust Analyzer found on NASA’s Europa Clipper spacecraft, finding life or its traces on icy moons might be easier than we thought,” added lead author Frank Postberg, a professor of planetary sciences at Freie Universität in Berlin. “Of course, this presumes that life is present and somehow finds its way into ice crystals originating from environments like a subsurface water reservoir.”