Asteroid collision led to the building of planets (artist concept)

2016-08-15 - Asteroids typically make headline news for close calls with Earth, and occasionally, for striking our planet. These mysterious and unpredictable space rocks are not always forces of destruction, though: in fact, they may be responsible for creating planets. Scientists think that planets like our own may have formed as a result of epic collisions between asteroids and larger celestial bodies called “proto-planets,” like the one depicted in this illustration.  (Credits: NASA, JPL-Caltech)