The NASA Discovery of the Carbon-Rich Asteroid OSIRIS-REx, which may have been transported to the Earth in the Formation of the First Planet
NASA scientists have finally revealed what OSIRIS-REx ferried back from the asteroid. After a seven-year journey, the sample from Bennu was returned to Earth in September. Scientists painstakingly cleaned and shipped the capsule to Johnson Space Center in Houston, Texas, making sure none of the rocks were contaminated by exposure to oxygen, moisture, or earthly bacteria, and they’re now analyzing the precious cargo.
Scientists had known that Bennu is a carbon-rich asteroid, but early analysis suggests that some of the returned sample is as much as 4.7% carbon — among the highest percentages of extraterrestrial carbon ever measured. Some of that carbon is bound up in carbonate minerals, which are made primarily of carbon and oxygen and are common in geological samples on Earth.
A video screen behind him showed a photo of asteroids outside the main sample container as the audience cheered. The analysis done by NASA shows that they contain water in hydrated clay minerals. The carbon is in the range of 4% to 5% by weight. “The carbon and water molecules are exactly the kinds of material that we wanted to find,” Nelson said. They are crucial elements in the creation of our own planet and they will assist us in figure out the origins of life.
Bennu has organic material made of compounds with carbon and hydrogen. On Earth, organic compounds are found in living organisms — but also in the absence of life. The organic patches in the Bennu samples look like a holiday tree when illuminated under ultraviolet light. A NASA Astrobiologist says that the device is loaded with organics. “This is incredible material.”
The sample of clay from Bennu have a resemblance to tiny fibers. Water locked inside those clay minerals might be ancient water from the dawn of the Solar System. Asteroids might have carried such water to the early Earth and helped to make it habitable.
Other microscopy images show hexagonal crystals that are likely sulfur-rich. Sulfur compounds play a crucial role in determining the rate at which rocks melt, as well as being involved in biologically interesting chemical reactions. The Bennu samples also contain iron-rich minerals with large flat surfaces, which might have helped catalyse chemical reactions early in the asteroid’s history.
It will take another few weeks before researchers know exactly how much of Bennu they captured. When OSIRIS-REx stretched out its robotic arm in 2020 to collect material from the asteroid’s surface, it came away with so much material that it overflowed the collecting mechanism.
It will be the most material to come back from outer space since the Apollo astronauts brought moon rocks to earth in the 1960s and 1970s. The two Hayabusa missions brought a little material back to Japan, but not much.