Newly released images captured last month by NASA’s Dawn spacecraft provide the best look yet of the central bright region of Occator Crater and reveal new evidence of the recent geologic activity believed to be responsible for some of the dwarf planet’s unique surface features.
According to Gizmodo and Scientific American, the images were taken during the probe’s most recent scientific orbit – its fifth since reaching Ceres during the spring of 2015. During this latest orbit, the spacecraft came to within 920 miles (1,480 km) of the dwarf planet’s surface, helping it to capture photographs while the angle of the sun was different from its previous flybys.
Prominently featured in those new pictures is a 57 mile (92 km) wide, 2.5 (4 km) deep region of Occator Crater which is home to bright spots that scientists believe may be the result of salts that were left behind after briny liquids bubbled up from below. The liquid froze, then sublimated (or rapidly changed directly into vapor), following an asteroid impact, leaving the salts behind.
The new image “captures the wonder of soaring above this fascinating, unique world that Dawn is the first to explore,” Marc Rayman, director and chief engineer for the Dawn mission at the Jet Propulsion Laboratory (JPL) in Pasadena, California, said in a statement issued late last week.
Additional images released as Dawn enters sixth science orbit
The Occator Crater image is one of thousands of new photographs snapped Dawn from its latest orbit, Rayman’s team explained. Another of the new images shows an approximation of what the dwarf planet’s colors would look like if viewed by the naked eye, doing so by combining images taken using red, green and blue filters during the probe’s first science orbit in 2015.
This picture, which was produced by officials at the German Aerospace Center (DAR) in Berlin, uses colors that were based on how Ceres reflects different wavelengths of light, JPL said. Other images captured close-ups of the craters known as Zadeni, Takel, Cozobi, Yalode and Kupalo.
Dawn entered its sixth science orbit on November 4, during which time it will raise its altitude to more than 4,500 miles (7,200 km) above the dwarf planet’s surface. Engineers have discovered a way to adjust the spacecraft’s orbit while its ion engine thrusts in the same direction in which it will be traveling, which will reduce its fuel use along the way.
Dawn is expected to reach this new orbit early next month, at which time it will begin working to collect new data and refine previously gathered measurements. It will also use its gamma ray and neutron spectrometer to start characterizing radiation from cosmic rays unrelated to Ceres, which will enable scientists to subtract “noise” from measurements and increase the preciseness of their data, according to JPL.
Image credit: NASA