Canadian-built laser technology aboard NASA spaceship OSIRIS-REx has successfully mapped the Bennu asteroid as it hurtles through deep space, in preparation for an eventual landing and sample extraction.
Launched on September 8, 2016, it took OSIRIS-REx more than two years to rendezvous with the asteroid, less than a half-kilometre in diameter and travelling more than 100,000 km/h.
“There’s instruments on the spacecraft that can take pictures of it to know what it looks like and to measure what it’s made of,” explains Dr. Tim Haltigin, Canada’s OSIRIS-REx mission manager at the Canadian Space Agency.
“And with the Canadian instrument called OLA, to measure really, really accurately what the shape is, so we can figure out where to grab a sample to bring it home. It’s going to be incredible.”
Short for OSIRIS-REx Laser Altimeter, the device’s high-energy laser is capable of accurate three-dimensional scans of the asteroid at a distance of seven kilometres, but also employs a secondary laser for rapid imagery at much closer proximities.
“Asteroids tell us about the history of the solar system and if you can go back and get a piece of an asteroid, essentially what you’ve done is gone back in time by four-and-a-half billion years,” says Haltigin of the incredible scientific opportunity.
“To help us understand what the early solar system is made of… because (asteroids) are really the leftover bits that went into forming planets, so it helps us learn how planets were made in the first place.”
Bennu was discovered in 1999 by the Lincoln Near-Earth Asteroid Research project. After reaching the asteroid, OSIRIS-REx spent one year orbiting and mapping it and on December 12, 2019 a landing spot was announced; a granular feature of a 140 meter crater dubbed Nightingale.
Orbital modelling of Bennu’s trajectory has produced cumulative odds of a one-in-2,700 chance the asteroid will collide with Earth between the years 2175 and 2199; in 2060 the asteroid is expected to pass within 750,000 km of Earth.
The OSIRIS-REx Laser Altimeter was built for the Canadian Space Agency by Brampton-based Maxar-MDA Corporation and is hybrid technology from previous contributions to the Phoenix Mars Lander and experimental satellite components for the US Air Force.
OSIRIS-REx will return to Earth in 2023.