At the Committee on SPAce Research (COSPAR) meeting held this week in Pasadena, NASA’s JPL scientists are presenting the latest information gathered by NASA’s Dawn space probe about the dwarf planet Ceres. In particular, there’s an attention on Occator Crater, the most famous crater thanks to its brightness due to the various bright spots made of salts inside it, now called faculae. In the next few months Dawn will finish its mission but will continue to collect data from the lowest orbit at only 34-35 kilometers (about 21 miles) of altitude.
The Dawn space probe is at the second extension of its mission orbiting the dwarf planet Ceres but that’s the last one because it’s running out of hydrazine, the fuel that feeds the thrusters that allow it to maintain its orientation and consequently also to communicate with the Earth. It’s not possible to say precisely when the thrusters will stop working but already in August Dawn will enter the critical period in which each maneuver could be the last.
After the bright spots were sighted on the dwarf planet Ceres, they quickly became its most iconic element and Occator Crater is the one that contains the group of spots with the highest sunlight reflection. Research showed that it’s above all sodium carbonate and ammonium chloride, salts exposed to the surface that represent remains of activities connected to water, perhaps even an underground ocean that existed in the past.
For the final phase of its mission, the Dawn space probe dropped to an altitude of 34-35 kilometers to collect the latest data. This means new high resolution photos but also data collected by other instruments such as the spectrometric ones detected by VIR (Visual and Infrared Spectrometer), provided by the Italian Space Agency.
Flying over Occator Crater, Dawn photographed the various bright spots within it, divided into the Cerealia Facula and the Vinalia Faculae. Carol Raymond of JPL, principal investigator in the Dawn mission, explained that the latest images of the crater and its surrounding areas went beyond expectations showing the complex geology that formed them. There are more information than those presented in December 2017 at the annual meeting of the American Geophysical Union.
Investigations around craters such as Occator but also other interesting craters such as Urvara are providing scientists with new information on past and present geological activities. They’re the most interesting part of the exploration of the dwarf planet Ceres and will continue even after the end of the Dawn space probe’s mission, studying the data it will send until the end.