Illustration comparing the planets of the Solar System and the Sun on the same scale. The planets are shown to scale relative to each other but their distances are not. From left to right the bodies ...

Roughly four and a half billion years ago the planet Theia slammed into Earth, destroying itself, melting large portions of our planet’s mantle and ejecting a huge debris disk that later pulled ...

A long-lost planet that helped create the Moon may have formed much closer to the Sun than scientists once thought, according to new research. Scientists have discovered that Theia, the ancient planet ...

Simulations reveal that Jupiter’s rapid growth disrupted the early solar system, creating rings where new planetesimals formed much later than expected. These late-forming bodies match the ages and ...

Add Yahoo as a preferred source to see more of our stories on Google. Artist’s impression of the planet Theia colliding with ancient Earth to create the moon. (MPS/Mark A. Garlick) Roughly four and a ...