Team develops new tools to help search for life in deep space

Are we alone within the universe? A solution to that age-old query has appeared tantalizingly inside attain because the discovery of ice-encrusted moons in our solar system with doubtlessly liveable subsurface oceans. However searching for proof of life in a frigid sea tons of of hundreds of thousands of miles away poses great challenges. The science gear used have to be exquisitely complicated but able to withstanding intense radiation and cryogenic temperatures. What’s extra, the devices should have the ability to take various, unbiased, complementary measurements that collectively might produce scientifically defensible proof of life.

To handle among the difficulties that future life-detection missions may encounter, a staff at NASA’s Jet Propulsion Laboratory in Southern California has developed OWLS, a robust suite of science devices not like every other. Brief for Oceans Worlds Life Surveyor, OWLS is designed to ingest and analyze liquid samples. It options eight devices—all automated—that, in a lab on Earth, would require the work of a number of dozen individuals.

One imaginative and prescient for OWLS is to make use of it to investigate frozen water from a vapor plume erupting from Saturn’s moon Enceladus. “How do you are taking a sprinkling of ice a billion miles from Earth and decide—within the one likelihood you have acquired, whereas everybody on Earth is ready with bated breath—whether or not there’s proof of life?” mentioned Peter Willis, the venture’s co-principal investigator and science lead. “We needed to create essentially the most highly effective instrument system you possibly can design for that state of affairs to search for each chemical and organic indicators of life.”

In June, after a half-decade of labor, the venture staff examined its gear—presently the dimensions of some submitting cupboards—on the salty waters of Mono Lake in California’s Japanese Sierra. OWLS discovered chemical and mobile proof of life, utilizing its built-in software program to determine that proof with out human intervention.

“We’ve demonstrated the primary era of the OWLS suite,” Willis mentioned. “The following step is to customise and miniaturize it for particular mission situations.”

Challenges, options

A key problem the OWLS staff confronted was the right way to course of liquid samples in space. On Earth, scientists can depend on gravity, an affordable lab temperature, and air stress to maintain samples in place, however these situations do not exist on a spacecraft hurtling by way of the solar system or on the floor of a frozen moon. So the staff designed two devices that may extract a liquid pattern and course of it within the situations of space.

Since it is not clear what type life may tackle an ocean world, OWLS additionally wanted to incorporate the broadest attainable array of devices, able to measuring a dimension vary from single molecules to microorganisms. To that finish, the venture joined two subsystems: one which employs a wide range of chemical evaluation strategies utilizing a number of devices, and one with a number of microscopes to look at visible clues.

OWLS’ microscope system could be the primary in space able to imaging cells. Developed in conjunction with scientists at Portland State College in Oregon, it combines a digital holographic microscope, which might determine cells and movement all through the quantity of a pattern, with two fluorescent imagers, which use dyes to watch chemical content material and mobile constructions. Collectively, they supply overlapping views at a decision of lower than a single micron, or about 0.00004 inches.

Dubbed Extant Life Volumetric Imaging System (ELVIS), the microscope subsystem has no shifting components—a rarity. And it makes use of machine-learning algorithms to each residence in on lifelike motion and detect objects lit up by fluorescent molecules, whether or not naturally occurring in residing organisms or as added dyes sure to components of cells.

“It is like searching for a needle in a haystack with out having to select up and look at each single piece of hay,” mentioned co-principal investigator Chris Lindensmith, who leads the microscope staff. “We’re mainly grabbing huge armfuls of hay and saying, ‘Oh, there’s needles right here, right here, and right here.'”

To look at a lot tinier types of proof, OWLS makes use of its Natural Capillary Electrophoresis Evaluation System (OCEANS), which basically pressure-cooks liquid samples and feeds them to devices that seek for the chemical constructing blocks of life: all styles of amino acids, in addition to fatty acids and natural compounds. The system is so delicate, it will probably even detect unknown types of carbon. Willis, who led improvement of OCEANS, compares it to a shark that may scent only one molecule of blood in a billion molecules of water—and likewise inform the blood sort. It could be solely the second instrument system to carry out liquid chemical evaluation in space, after the Microscopy, Electrochemistry, and Conductivity Analyzer (MECA) instrument on NASA’s Phoenix Mars Lander.

OCEANS makes use of a method known as capillary electrophoresis—mainly, working an electrical present by way of a pattern to separate it into its parts. The pattern is then routed to a few sorts of detectors, together with a mass spectrometer, essentially the most highly effective device for figuring out natural compounds.

Sending it residence

These subsystems produce huge quantities of knowledge, simply an estimated 0.0001% of which might be despatched again to faraway Earth due to information transmission charges which can be extra restricted than dial-up web from the Eighties. So OWLS has been designed with what’s known as “onboard science instrument autonomy.” Utilizing algorithms, computer systems would analyze, summarize, prioritize, and choose solely essentially the most attention-grabbing information to be despatched residence whereas additionally providing a “manifest” of data nonetheless on board.

“We’re beginning to ask questions now that necessitate extra subtle devices,” mentioned Lukas Mandrake, the venture’s instrument autonomy system engineer. “Are a few of these different planets liveable? Is there defensible scientific proof for all times moderately than a touch that it is likely to be there? That requires devices that take numerous information, and that is what OWLS and its science autonomy is ready as much as accomplish.”