Mars and Earth have very different histories. A simple example: Earth is mostly covered with water, while Mars lost its water in the distant past. But scientists also know that the elements on Mars have different isotopes, or atomic…
Scattered in orbits around the sun, pieces of rock left by the dawn of the solar system. Most of these objects, called planetoids or asteroids - meaning “star-like” - orbit between Mars and Jupiter in a group known as the main asteroid…