University of Alberta’s expert assist select samples to bring back from Mars
A University of Alberta researcher is among a group of scientists choosing which samples NASA’s rover Perseverance will gather on Mars to bring back for analysis on Earth.
For this mission, “return sample scientist” Chris Herd, a professor in the Department of Earth & Atmospheric Sciences and curator of the U of A’s Meteorite Collection, will help determine which samples could answer the most questions about Mars, including whether it has ever housed life.
“It’s absolutely phenomenal for me to be involved in such a huge mission, where we get to explore and get information about the rocks and the geology while at the same time sampling and looking forward to bringing those samples back,” Herd says. “That’s what sets this mission apart.”
Perseverance, which has been exploring Mars since 2020, can only bring back 30 samples about the size of a piece of chalk — each weighing up to about 10 grams. The highest quality samples are sealed and stored airtight on Perseverance to await handoff to a future mission to bring them back to Earth. A backup of each sample remains in a depot on Mars.
Selecting information-rich samples is key. Modern technology and innovative tools mean the limited sample materials available shouldn’t be an issue.
“There are ways we can analyze a sample that give us incredible detail about when the rock formed, how it was modified, whether there’s any organic matter that could be evidence of life,” says Herd. “There’s a host of things we can tell from tiny amounts.”
Tools aboard Perseverance record the location of samples and gather information about the environment surrounding each one, giving researchers invaluable context. Researchers will compare the samples with some of the at least 175 Martian meteorites discovered on Earth to offer a better picture of what has happened on the planet. The sedimentary samples will fill a gap in our knowledge about Martian geology, as we currently have no sedimentary rocks from the Red Planet.
The earliest the samples will come back for analysis is 2033. A facility will be needed to house and study the samples appropriately and safely. Researchers will need to protect our environment from potentially harmful martian contaminants, while also avoiding Earthly contamination of the samples.
“There’s a lot that we have to do to make sure we don’t contaminate the samples with signatures of life from Earth and misinterpret that signature as life on Mars,” Herd says. “We need to get this right because this is answering a huge question.”