The National Aeronautics and Space Administration’s (Nasa’s) deep-space explorer Osiris-Rex flew on Monday to within 19km of its destination, a skyscraper-sized asteroid believed to hold organic compounds fundamental to life as well as the potential to collide with Earth in about 150 years.
Bennu, a rocky mass roughly a half a kilometre wide and shaped like a giant acorn, orbits the sun at roughly the same distance as Earth and is thought to be rich in carbon-based organic molecules dating back to the earliest days of the solar system. Water, another vital component to the evolution of life, may also be trapped in the asteroid’s minerals.
Scientists believe that asteroids and comets crashing into early Earth delivered organic compounds and water that seeded the planet for life, and atomic-level analysis of samples from Bennu could help prove that theory.
Scientists estimate there is a one-in-2,700 chance of the asteroid slamming catastrophically into Earth 166 years from now. That probability ranks Bennu number two on Nasa’s catalog of 72 near-Earth objects potentially capable of hitting the planet.