Scripps Institution of Oceanography Helps Deliver Goods on Martian Meteorites
The Scripps research team analyzed meteorites found at sites in Antarctica and Africa that formed on Mars more than a billion years ago. Perhaps 11 million years ago, a large meteor hit the planet, shearing away some of the Martian crust and sending rocks into space -- some of which then landed on Earth in the form of meteorites.
Source: timesofsandiego.com