Discovery of Ancient Grains
Scientists analyzing material from the asteroid Bennu have identified particles known as “stardust.” These grains are remnants from other stars, predating the formation of our solar system. Researchers say their presence indicates that Bennu likely formed after colliding with a larger asteroid during the solar system’s earliest stages. The unique appearance of the grains, unlike anything native to our solar system, makes them distinguishable under specialized instruments.
OSIRIS-REx Mission’s Contribution
The samples were delivered to Earth by NASA’s OSIRIS-REx spacecraft, a mission led in part by the University of Arizona. Bennu, believed to be about 4.6 billion years old, has endured impacts from micrometeorites throughout its history. These collisions left distinct signatures in the material now under study, helping scientists reconstruct the asteroid’s past.
Advanced Laboratory Analysis
Researchers at the University of Arizona’s Kuiper-Arizona Laboratory for Astromaterials Analysis are using high-precision instruments capable of probing chemical structures at the nanometer scale. This technology allows them to detect elemental compositions and identify the origins of exotic grains. The data offers rare insight into processes that occurred before our solar system fully developed, making Bennu a time capsule of cosmic history.
Why It Matters
The findings deepen our understanding of how planets and asteroids formed, highlighting how ancient stellar material continues to shape our solar neighborhood. By studying Bennu’s stardust and collision history, scientists not only piece together the past but also gain clues about the evolution of Earth and the origins of life.