NASA to Sample Asteroid Said to Contain Building Blocks of Life
NASA’s OSIRIS-REx spacecraft has been in orbit of the asteroid Bennu since late 2018, and it’s almost time for the main event: collecting a sample from the surface. Researchers have used the last few years to get familiar with Bennu, and that has led to six studies that were just published in the journals Science and Science Advances that describe the environment and composition of the space rock. We know what OSIRIS-REx is likely to scoop up from the asteroid. Yes, rocks, but they’re exciting rocks.
One study, led by Amy Simon from NASA’s Goddard Space Flight Center, shows that carbon-bearing minerals are widespread on Bennu, including at the Nightingale landing zone where OSIRIS-REx will touch down. Scientists on Earth are already planning experiments on these materials that could help us understand the origin of water and life on Earth.
Another study focused specifically on carbonate minerals (a salt of carbonic acid), which is visible in veins crisscrossing some boulders. Carbonates are usually produced in systems that have both water and carbon dioxide, leading scientists to conclude that Bennu’s long-destroyed parent body contained water. The size of the carbonate veins suggests the water system was large, on the order of miles. Again, these materials are widespread and may be present in the samples OSIRIS-REx picks up, which has researchers excited.
Part of the probe’s mission before collecting its sample was to map the surface in detail. This allowed NASA to study the asteroid’s topography and choose a landing location. With data acquisition complete, the agency has created the most detailed map ever of an asteroid with a resolution of 20cm per pixel. The video below takes you on a tour of Bennu created with a combination of photos and laser altimeter data.
When OSIRIS-REx descends on October 20th, it will tap the surface and use a blast of compressed nitrogen gas to (hopefully) blow regolith into the sample container. Of course, numerous asteroids fall to Earth every day, but they’ve been scorched by their journey through the atmosphere. Sampling Bennu allows scientists to study primordial material from the early solar system. One of the new studies suggests that the material around Nightingale is even better for this purpose than expected. The Nightingale site is “spectrally red” compared to much of the surface. That indicates the material was only recently uncovered and exposed to space, making it super-pristine.
The samples from OSIRIS-REx should be back on Earth in September 2023. Until then, we’ll have to root for the probe from a few million miles away.