MONTREAL — New research on a sample from the asteroid Bennu is shedding light on its origins and the history of our solar system. A small portion of this sample is expected to arrive in Canada soon. Studies published in Nature Astronomy and Nature Geoscience last week provide insights into the granules collected during NASA's OSIRIS-REx mission, which returned to Earth in September 2023.

The research, which includes contributions from Canadian scholars, indicates that Bennu is a near-Earth asteroid. However, its composition suggests that the parent asteroid it originated from contains materials sourced from across the solar system. "What they've done is they've looked at the origin and the formation and evolution of the Bennu sample to understand its history," said Dr. Patrick Hill, a program scientist at the Canadian Space Agency.

As Canada prepares to receive its share of the sample for scientific study, the Canadian Space Agency (CSA) is set to curate about four percent of the total 122 grams of material collected, which amounts to just under five grams. This will make Canada the fifth country to curate samples collected in space. The CSA's share is expected to arrive no earlier than 2026.

"The CSA is building its capacity to curate its first sample collected in space," Hill noted. Construction of a clean room south of Montreal began in January 2025. The sample will be transferred in a carefully coordinated effort with NASA.

Hill emphasized the importance of protecting the sample from contamination. "This area is quite niche because of the astral materials and there’s a lot of requirements that we have to make sure are implemented to ensure that we are not contaminating the sample," he said. This includes safeguarding it from water, organic molecules, and plastics. "The goal of these missions is not to modify the material while it’s here on Earth," he added.

The OSIRIS-REx mission, which launched in 2016, aimed to collect material from Bennu's surface to provide insights into the solar system's formation. The spacecraft began orbiting Bennu in 2018 and successfully collected a sample in 2020. It returned to Earth in 2021, with the sample capsule landing in the Utah desert.

Canada contributed a laser altimeter tool, known as OLA, which measured altitude and distance. This tool allowed for extensive surveying of Bennu, resulting in billions of measurements over two years. It played a crucial role in identifying the optimal location for sample collection.

Recent studies revealed that Bennu was formed from a larger parent asteroid that was destroyed by a collision in the asteroid belt between Mars and Jupiter. This parent body originated in the outer solar system and incorporated materials from various locations, including beyond our solar system. The analysis of the sample has shown the presence of stardust grains with compositions that predate the solar system.

Hill remarked, "We have a lot of meteorites that provide a lot of information about this sort of area of research, but these missions are great because you go and get the sample and you bring it back. So it’s not altered by traveling through the atmosphere and modification on the Earth’s surface, so it allows us to really look at the pristine material in detail."

Another study indicated that Bennu has undergone significant transformations over time due to interactions with water and exposure to the harsh conditions of space.