Find out everything there is to know about Mars and stay updated on the latest Mars news with the comprehensive articles, interactive features and Mars pictures at LiveScience.com. Learn more about this fascinating planet as scientists continue to make amazing discoveries about Mars.
Astrobiologist and author David Grinspoon has been a student of the planets his entire life. He talks to Space.com's @SteveSpaleta about what we can learn about Earth from studying our solar system’s planets.
Many meteorites found on Earth are remnants of one titanic solar-system collision that took place more than 460 million years ago. But researchers have found the composition of space rocks before then are quite different than those today.