An asteroid treasure box lands on Earth on Sunday — and Canada will get a piece of it

A spacecraft that has travelled more than 950 million kilometres is dropping off a care package on Sunday: samples from an asteroid that lies more than 100 million kilometres from Earth.

NASA's OSIRIS-REx (Origins, Spectral Interpretation, Resource Identification, Security-Regolith Explorer) launched in 2016 destined for an asteroid named Bennu. Its main mission: to stick an arm out, "high-five" the asteroid and then vacuum up some of the debris, referred to as "touch and go." 

It successfully did so in 2020. Now, the rocky samples — roughly 250 grams in total, the largest ever to return to Earth — are on their way to be studied by science teams, including those from Canada.

That's thanks to our contribution of the OSIRIS-REx Laser Altimeter (OLA), an instrument that mapped out the asteroid in 3D in order to find a good place for the sample collection.

"It's tough to put into words," said Tim Haltigin, planetary senior mission scientist with the Canadian Space Agency (CSA) earlier this week. "September 24, 2023, always used to be this hypothetical date off in the future…. So, to think we're just a few days away is unbelievable."

Haltigin is just one of a contingent of Canadian scientists and engineers who worked on the OLA, and he's anxiously awaiting its return.

"It's almost like sending one of your kids off to college: You've done everything you can, you've worked as hard as you can for many years, you've put in a lot of love and effort," he said.

"And you just send it on its way, hoping that you've done your best and that it'll do its best. And in this case, we've had just an incredible mission."

Now that college kid is returning home, not with dirty laundry, but with 4.5-billion-year-old rubble that could tell us more about how our solar system came to be.

On Sunday, the spacecraft will release its sample capsule roughly four hours — or 100,000 kilometres — from the planet. The capsule will travel through the atmosphere at roughly 44,500 km/h before touching down in the Utah desert around 10:55 a.m. EDT.

From there, it will be taken by helicopter to a clean lab and transported to its home at NASA's Johnson Space Center in Houston, Texas, the next day. NASA plans to reveal the sample on Oct. 11.

But that won't be the end of the spacecraft — its mission has been extended and renamed the OSIRIS-APEX (OSIRIS-APophis EXplorer). It will fly by another asteroid named Apophis, a 370-metre rocky body that will come within 32,000 kilometres of Earth in 2029.

Once again, the OLA will map out the asteroid, while other data is collected to see how it changes as it nears the sun.

Getting the samples was a seven-year process. OSIRIS-REx blasted off from Cape Canaveral on Sept. 8, 2016, arrived at Bennu in 2018, collected its sample in 2020 and began its return home in 2021.