NASA’s Dawn Spacecraft Orbits Dwarf Planet Ceres

Scientists hope to solve mystery of bright spots on the largest object between Mars and Jupiter

After a voyage of 3 billion miles, NASA’s Dawn spacecraft safely orbited the dwarf planet Ceres today—the largest object in the asteroid belt between Mars and Jupiter.

In a $473 million mission, the spacecraft is now set to begin 16 months photographing the distant world for evidence of an ancient ocean that may be preserved as ice under its crust. Scientists also hope to learn the secret of two dazzling bright spots in a crater on Ceres—considered unique in the solar system—which have baffled astronomers since they were discovered last month.

“This is now Dawn’s permanent home,” said mission director and chief engineer Marc Rayman at JPL. “It is going to be there forever.”

The probe is the first spacecraft to orbit a dwarf planet—a group that includes Pluto and three other small worlds—and the first to successfully rendezvous with two different celestial bodies. From 2011 to 2012, the spacecraft explored the giant asteroid Vesta, beaming back 30,000 images of the previously unexplored orb.

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