Researchers at the University of Winnipeg (U of W) are playing a prominent role in a historic NASA-led mission to collect and study samples from a near-Earth asteroid.

A sample of 4.5-billion-year-old rock fragments and dust from the asteroid Bennu made a two-week stop at the U of W’s Centre for Terrestrial and Planetary Exploration (C-TAPE) in early January.

Geography professor and C-TAPE director Dr. Ed Cloutis is a globally recognized expert in hyperspectral analysis, a non-destructive technique similar to photography with the capacity to register wavelengths of light invisible to the human eye.

His team’s analysis will help determine what kinds of complex organic molecules could have been present billions of years ago on the asteroids that crashed together to form Earth.

“Living organisms are composed of amino acids, DNA and all this other stuff,” Cloutis says. “By looking at these asteroids, we can figure out how close(ly) ... the chemistry that went on in these asteroids get(s) us to the complex molecules that we need to form life.”

The mission

NASA launched the OSIRIS-REx sample return mission on Sept. 8, 2016 from Cape Canaveral, Fla. The spacecraft completed its 6.2-billion-kilometre round trip to Bennu and back on Sept. 24, 2023, jettisoning its sample capsule into the Earth’s atmosphere before setting off to study the asteroid Apophis.

OSIRIS-REx is only the third successful asteroid sample return mission in history and the first led by NASA.

In terms of sample volume, it’s also the most ambitious. Japan’s Hayabusa2 mission returned 200 milligrams of the asteroid Ryugu. The total Bennu sample is an astonishing 250 grams.

U of W alum Dr. Jessica Stromberg is a senior research scientist at the Commonwealth Scientific and Industrial Research Organization in Australia. She says the engineering challenges involved in sample collection are compounded by the nature of asteroids’ “fluffy,” packing-peanut-esque surfaces.

Bringing back larger samples “involves a lot more complexity in terms of engineering,” she says. To “land there, sit there, collect something, put it in ... every single one of those steps increases the risk of something failing. On a first go, bringing anything back is a big win.”

Stromberg says missions like this can “unite folks globally” by providing opportunities to advance humankind’s collective understanding of “how we ended up (on Earth).”

“Obviously there’s a lot of things going on in the world that you could argue are more pressing, but (the mission) does create a sense of something we can all get behind together,” she says.

“Big missions to deep space and other areas (are) something that require a collaborative effort of multiple countries, multiple organizations ... it’s really, really exciting to see it all come together.”

Opportunities

Analyzing the sample is a global effort involving more than 200 scientists at several dozen institutions.

Due in part to its contribution of OSIRISREx’s Laser Altimeter component, the Canadian Space Agency (CSA) was allocated four per cent of the overall sample. This sample portion is what’s being circulated between a research chain of Canadian universities, including the U of W.

Cloutis says the U of W is one of only two Canadian universities able to give students the “unique opportunity” of a hands-on role in the NASA mission. A half-dozen undergraduate and master’s students are working alongside Cloutis and lab manager Dan Applin to collect, analyze and publish data about the sample.

“Being involved in something like this certainly shows the rest of the world that we’re a player right now,” Cloutis says. “We’ve got the chops. We’ve got the expertise. We’ve got the equipment. This will definitely help us get in on future missions.”

The CSA tapped C-TAPE for its sample-analysis team because it’s one of the only facilities in the world with the right equipment to perform hyperspectral analysis without exposing the material to Earth’s atmosphere.

“When a meteorite lands on Earth, it immediately starts to get contaminated by microbes and other stuff in the atmosphere,” Cloutis says. “This asteroid sample, by contrast, is a pristine slice of what’s out there in space.”

Ensuring that the asteroid material only ever comes in contact with nitrogen, an inert gas that won’t react with the sample, is a defining characteristic of the sample preparation process.

Opening the sample return capsule’s outer shell was a carefully choreographed two-day operation carried out inside a nitrogen purge custom-built for the occasion.

Accessing the bulk of the sample took more than three months, as custom tools had to be designed and built after two of the Touch-and-Go Sample Acquisition Mechanism’s 35 fasteners became stuck.

Cloutis has a reassuringly matter-of-fact attitude about the delicate nature of the cargo. “It’s not super fancy,” he says of handling the sample. “I mean, we have a sealed box with a door on it.”

What comes next

Analysis of Bennu’s geochemical properties will provide a crucial window into the kinds of organic molecules available 4.5 billion years ago on an infant Earth. Cloutis says future work seeking to fill in gaps in our understanding of how life formed on Earth will involve further asteroid sample retrieval, lab experiments and continuing the search for life on Mars.

Stromberg says the expertise she developed studying with Cloutis made her career as a geologist possible. As an undergraduate, she helped Cloutis research Manitoban sites with similar geology to Mars. She says the experience got her “hooked” on the idea of geological analysis as a source of insights about planetary biology.

After earning her PhD at the University of Western Ontario, Stromberg returned to the U of W as a postdoctoral fellow, collaborating with Cloutis and Applin on hyperspectral analysis of meteorites and Mars analogues. She says experiences like hers point to the impacts on students’ careers provided by opportunities like working on OSIRIS-REx.

“That’s one of the big things out of this. It’s training the next generation of scientists in this space,” she says. “You can see that Ed’s students are working on other missions now or working in labs in the US or other places. People don’t assume this sort of facility or lab or work will be happening at the U of W, but it really is a world-class space.”

Published in Volume 78, Number 15 of The Uniter (January 25, 2024)