The Survival Timeframe of Asteroids: NASA Expert Uncovers the Truth

Scientists are studying the age and lifespan of asteroids like Bennu, which was recently sampled by NASA's OSIRIS-REx spacecraft. Asteroids formed from the protoplanetary disk 4.5 billion years ago and can break up due to spinning, thermal stress, or collisions. The largest intact asteroids are around the same age as the solar system, while smaller pieces can be considered younger. Some asteroids may last as long as the rocky inner planets, between 8 billion and 10 billion years. Once an asteroid fragments into small pieces, they are reclassified as meteoroids. The rubble pile asteroids, like Bennu, are held together by their own gravity and are tough, except when they collide with a planet or fall into the sun.