As another spacecraft prepares to land on Mars, the Dawn spacecraft recently ended its mission to explore two of the largest worlds in the asteroid belt and it has succeeded well beyond expectations, starting a new era in the exploration of the Solar System’s small worlds.
As the age of robotic planetary exploration began, as early as 1964, mission plans were drawn up to explore the main asteroid belt between Mars and Jupiter, to characterize these worlds which are regarded as leftovers from the formation of the Solar System. These “leftovers” promise to answer many questions about how the Solar System and its worlds, including Earth, formed, and possibly even how Earth came to bear life.
The Pioneer 10 and 11 spacecraft passed through the asteroid belt on their way to Jupiter and demonstrated that space probes could navigate safely through the belt even though thousands of small, rocky worlds were orbiting in the belt. After the Voyager probes passed through the asteroid belt, the Comet Rendezvous and Asteroid Flyby (CRAF) probe was planned to fly by asteroids and explore a comet before it was canceled in 1992 due to budget cuts.
The two Pioneer spacecraft – via NASA