In a historic moment, scientists have obtained their first glimpse of the sample collected from the near-Earth asteroid Bennu, and the results have exceeded their expectations.
On September 26, when they opened the canister containing the precious sample, researchers were greeted with an unexpected find—an abundance of dark, fine-grained material covering the interior of the container’s lid and base, surrounding the mechanism used to collect the extraterrestrial rocks and soil. This serendipitous discovery promises to provide valuable insights into the asteroid’s composition before the primary sample is subjected to analysis.
The momentous landing of the Bennu sample in the Utah desert on September 24 marked the culmination of NASA’s seven-year OSIRIS-Rex mission. This mission involved a journey of approximately 200 million miles from Earth to Bennu, where the spacecraft briefly touched down on the asteroid before returning to Earth to drop off the sample. In total, the spacecraft covered a staggering distance of about 3.86 billion miles.
The day after its arrival, the mission team promptly transported the canister to NASA’s Johnson Space Center in Houston, home to a dedicated clean room designed for the meticulous analysis of cosmic samples.
What the Bennu Sample Could Reveal
Asteroids are remnants from the formation of the solar system, offering a window into the chaotic early days when planets took shape. Understanding their composition and orbits is crucial, not only for gaining insights into the past but also for safeguarding our planet from potential asteroid impacts.
During OSIRIS-REx’s mission, it deployed its Touch-and-Go Sample Acquisition Mechanism (TAGSAM) head to disturb the surface of Bennu and collect a sample in October 2020. To everyone’s surprise, so much material was gathered that particles could be seen drifting into space before the head was safely stowed in the canister.
This unexpected abundance of material outside the TAGSAM head has led scientists to conduct an initial analysis of this material before delving into the bulk of the sample concealed within the mechanism head. The sheer volume of material has pleasantly delayed their progress.
Christopher Snead, deputy OSIRIS-REx curation lead, stated, “The very best ‘problem’ to have is that there is so much material, it’s taking longer than we expected to collect it.”
The actual asteroid sample will remain a mystery until October 11 when NASA plans to unveil it during a live broadcast. The TAGSAM head will be moved to a specialized glovebox for careful disassembly, revealing the hidden sample.
In the meantime, a preliminary examination of the material taken from outside the TAGSAM head is already underway. This quick-look analysis could offer initial findings from Bennu’s material. Lindsay Keller, an OSIRIS-REx sample analysis team member, emphasized their advanced analytical techniques, from scanning electron microscopes to X-rays and infrared instruments, enabling a deep dive into the sample’s chemical composition.
This comprehensive approach aims to detect hydrated minerals, organic particles, and specific types of minerals present on the asteroid, providing vital information about its composition.
“You’ve got really top-notch people and instruments and facilities that are going to be hitting these samples,” Keller stated.
The initial analysis will provide valuable insights to guide the examination of the bulk sample collected from Bennu.
Scientists believe that asteroids like Bennu may have delivered essential elements, including water, to Earth during its early formation. The pristine sample collected could hold the answers to long-standing questions about the origins of our solar system.
Meanwhile, the spacecraft responsible for delivering the sample, now known as OSIRIS-APEX, is en route to study the near-Earth asteroid Apophis, which will come close enough to Earth in 2029 to be visible to the naked eye.
