NASA’s Dawn Spacecraft on the Way to Its Lowest-Ever Orbit around Ceres

NASA’s Dawn spacecraft is maneuvering to its lowest-ever orbit for a close-up examination of the dwarf planet Ceres.

This artist’s concept shows NASA’s Dawn spacecraft arriving at Ceres. Image credit: NASA / JPL-Caltech.

In early June, Dawn will reach its lowest-ever and final orbit above Ceres.

Soon after, the spacecraft will begin collecting images and other science data from an unprecedented vantage point.

This orbit will be less than 30 miles (50 km) above the surface of the dwarf planet — 10 times closer than the spacecraft has ever been.

Dawn will collect gamma ray and neutron spectra, which help scientists understand variations in the chemical makeup of Ceres’ uppermost layer.

That very low orbit also will garner some of Dawn’s closest images yet.

On the way to its lowest-ever and final orbit, Dawn is observing Ceres and returning new compositional data (infrared spectra) and images of the dwarf planet’s surface, such as this dramatic image of Ceres’ limb. This picture is one of the first images returned by Dawn in more than a year. The spacecraft captured this view on May 16, 2018 from an altitude of about 270 miles (440 km). The large crater near the horizon is about 22 miles (35 km) in diameter. It is located at about 23 degrees north latitude, 350 degrees east longitude, not far from a series of tholi (small mountains) that include Kwanzaa Tholus. The midsize crater in the foreground is located about 75 miles (120 km) from the large crater. This rough landscape suggests these features are on top of ancient terrains. Image credit: NASA / JPL-Caltech / UCLA / MPS / DLR / IDA.

The transfer from Dawn’s previous orbit to its final one is not as simple as making a lane change.

Dawn’s operations team worked for months to plot the course for this second extended mission of the spacecraft, which is propelled by an ion engine.

Engineers mapped out more than 45,000 possible trajectories before devising a plan that will allow the best science observations.

“The team is eagerly awaiting the detailed composition and high-resolution imaging from the new, up-close examination,” said Dawn’s principal investigator Dr. Carol Raymond, from NASA’s Jet Propulsion Laboratory.

“These new high-resolution data allow us to test theories formulated from the previous data sets and discover new features of this fascinating dwarf planet.”