A group of Canadian scientists is eagerly anticipating the arrival of a unique package from outer space – a capsule containing matter collected from the surface of an asteroid dating back to the early history of the solar system. NASA’s OSIRIS-REx spacecraft, which was launched from Florida seven years ago, is expected to drop the capsule into Earth’s atmosphere on September 24.
The sample comes from Bennu, formerly known as near-Earth object 101955, a frozen rock approximately 500 meters in diameter, situated around 450,000 kilometers from Earth. OSIRIS-REx has closely orbited Bennu’s surface, collected a sample, and is now en route to deliver the precious cargo back home.
Canadian-built lasers played a significant role in guiding OSIRIS-REx to Bennu and producing a detailed relief map of the asteroid, providing the most precise asteroid model to date. This helped scientists observe fractures and details in the rocks, offering insights into the asteroid’s composition.
Bennu was chosen as the target for several reasons. It was at an accessible distance, large enough for a spacecraft to orbit, and considered “primitive,” preserving its original characteristics since its formation billions of years ago. By studying Bennu, scientists aim to gain knowledge about the early history of the solar system and Earth’s formation, as it can provide a glimpse into the past.
The asteroid is expected to provide samples from an older part of the solar system, unaffected by the changes caused by heat. Additionally, Bennu’s rich carbon content could hold organic compounds, which might provide clues about the origins of life on Earth.
Although this won’t be the first time asteroid samples have been brought to Earth, the yield from OSIRIS-REx is expected to be much larger, estimated to range from 60 grams to two kilograms. Canadian scientists are among the recipients of Bennu samples due to Canada’s significant investment in the OSIRIS mission.
Before studying the samples, scientists will carefully rehearse protocols for handling these precious materials. They hope the Bennu samples will lead to numerous research papers and further expand our understanding of the solar system’s history.
Once OSIRIS-REx completes its mission with Bennu, it will head to study Apophis, a 370-meter-diameter asteroid that will come close to Earth in 2029. The spacecraft will use its thrusters to dislodge dust and small rocks from Apophis’s surface and relay information back to Earth before concluding its journey.