NASA has finally unveiled the total amount of asteroid sample that was brought back from Bennu to Earth last fall. The sample weighs 4.29 ounces, which is equivalent to 121.6 grams. While this may seem like a small amount, it is actually 20 times greater than the amount of asteroid material previously returned to Earth by Japanese sample return missions.
To put the size of the sample into perspective, it is only slightly more than one-half cup of sugar or a box of 100 paper clips. It is about the same mass as a small avocado, and you can’t even smear it on toast. Considering the efforts and resources that NASA and its partners put into retrieving this sample, it may seem like a small payoff. The Goddard Space Flight Center, University of Arizona, and Lockheed Martin collaborated to build the OSIRIS-REx spacecraft, which cost $800 million. The spacecraft was launched in September 2016 on an Atlas V rocket, adding an additional cost of $183.5 million. NASA has also spent $200 million on mission operations.
In total, NASA has invested $1.2 billion and nearly a decade of work to retrieve a volume of asteroid dust that could fit comfortably within a small can of tuna. However, despite the small size, this sample holds great scientific value. Scientists will study the organics and other materials in this asteroid dust to gain insights into the origin of life and the conditions that existed in our Solar System’s early days. Even a small amount of material can yield meaningful results when examined under an electron microscope.
The sample retrieval from Bennu exceeded the mission’s minimum requirement of 60 grams, making the OSIRIS-REx mission an unqualified success. This achievement is a testament to the hard work and dedication of the engineers and technicians at Johnson Space Center in Houston who overcame challenges to open the sample container and reveal the tiny treasure in January.
In the coming weeks, some of the Bennu material will be packaged and distributed to researchers for further study. A cohort of over 200 scientists from around the world, including researchers from various US institutions, the Japan Aerospace Exploration Agency, and the Canadian Space Agency, will explore the properties of the regolith. However, NASA plans to reserve about 70 percent of the material for future study.
While the sample size may be small, its significance in advancing our understanding of the Solar System and the origins of life cannot be understated. The efforts and resources invested in the OSIRIS-REx mission have paid off, and scientists eagerly await the discoveries that will be made from this precious asteroid sample.
