The Lifespan of an Asteroid: How Long Can They Last?

Scientists are studying the age and lifespan of asteroids like Bennu to understand their formation and longevity. Asteroids formed from the protoplanetary disk 4.5 billion years ago and some have remained intact since then. However, asteroids can break up due to spinning, thermal stress, or collisions with other celestial objects. The largest asteroids may last as long as the rocky inner planets of the solar system, while smaller fragments become meteoroids or reassemble into rubble pile asteroids. The upcoming analysis of samples from Bennu will provide further insights into the history and structure of these celestial bodies.