NASA’s OSIRIS-REx spacecraft has discovered materials older than the Sun in samples collected from the Bennu asteroid. These findings provide scientists with a unique window into the universe before the formation of the Solar System.
The samples, taken from Bennu, located about 200 million miles from Earth, revealed “presolar grains” or stardust formed billions of years ago around stars that had exhausted their lifespans. Researchers note that these particles are chemically primitive and likely originated in the outer regions of the Solar System, possibly beyond Saturn’s orbit, rather than near the Sun.
Prof. Jessica Barnes from the University of Arizona stated, “Bennu’s main body contains materials formed in the distant reaches of the early Solar System, even before our young Sun was born.”
Chemical analyses also revealed organic matter from interstellar space, as well as materials that formed near the Sun at high temperatures and were later transported to the outer regions. Prof. Sara Russell from the Natural History Museum in London explained, “These grains have remained almost entirely unchanged for billions of years. They help us understand the environment in which planets were born.”
NASA’s OSIRIS-REx spacecraft briefly touched Bennu’s surface in 2020 and collected about 120 grams of samples, which safely returned to Earth in 2023.
Scientists emphasize that these new findings provide unprecedented insights into the birth of the Solar System and the formation of planets. Previous studies had also revealed that Bennu contains building blocks of life.
