With a Canadian Assist OSIRIS-REx Scientists Have Selected Four Candidate Locations on Asteroid Bennu For Sample Collection

The NASA led OSIRIS-REx mission is exceeding scientists expectations and now they have to make the difficult decision of where to land the spacecraft from four candidate sites on asteroid Bennu to collect samples.

Canada’s contribution to the spacecraft is the OSIRIS-REx Laser Altimeter, know as OLA. According to the Canadian Space Agency (CSA) “it is equipped with two lasers that scanned the asteroid’s surface to produce detailed images of the boulders, craters and other geological features at each of the four sites. These maps will be crucial in helping mission scientists select the safest and most scientifically interesting of the approximately 10-metre-wide candidates – known as Nightingale, Kingfisher, Osprey, and Sandpiper.”

The CSA further stated that “OLA’s high-resolution results follow the activation of the instrument’s low-energy laser transmitter (LELT) at the beginning of July 2019. The LELT is designed to fire 10,000 light pulses per second at the asteroid, and operates at a range of less than 1 km above Bennu’s surface.”

The same area of asteroid Bennu's surface – a potential sample site known as Sandpiper – was measured by each of OLA's lasers. OLA's high-energy laser transmitter (HELT) captured its measurements from a distance of 5 kilometres (top right). OLA's low-energy laser transmitter (LELT) captured the details of the site's boulders and craters from a distance of only 700 metres (bottom right). Image creation: Michael Daly, Centre for Research in Earth and Space Science, York University. — The same area of asteroid Bennu’s surface – a potential sample site known as Sandpiper – was measured by each of OLA’s lasers. OLA’s high-energy laser transmitter (HELT) captured its measurements from a distance of 5 kilometres (top right). OLA’s low-energy laser transmitter (LELT) captured the details of the site’s boulders and craters from a distance of only 700 metres (bottom right). Image creation: Michael Daly, Centre for Research in Earth and Space Science, York University (Credit: NASA/University of Arizona/Canadian Space Agency/York University/MDA)

High-resolution maps of the four potential sample sites will allow OSIRIS-REx scientists to:

Assess the safety and accessibility of each region.
Locate landmarks that will help the spacecraft navigate during sample collection.
Identify areas of fine-grained material compatible with OSIRIS-REx’s sampling device.

Sampling is set to occur in 2020 after the spacecraft successfully rehearses sampling manoeuvres.