Since its takeoff from Cape Canaveral, Florida, on September 27, 2007, the US space probe Dawn is on its mission to explore the small bodies Vesta and Ceres in the asteroid belt between Mars and Jupiter. The NASA-mission aims at investigating the formation and evolution of these bodies to find clues to the solar system’s early history. The journey through the inner solar system, in the course of which Mars was passed in February 2009, was successfully completed by Dawn and in July 2011 its first target, the asteroid Vesta, was reached. For a year, the probe collected scientific data of Vesta before starting the journey for two and a half years to its second mission object, the dwarf planet Ceres. At the beginning of 2015 the probe has reached the target; since then the instruments continuously transmit data about the properties of Ceres, while further approaching its surface.
Space probe Dawn approaching Vesta (artist's impression)
Image Credit: NASA/JPL-Caltech
The camera experiment on board Dawn is the Framing Camera (FC) which was developed in cooperation between the Max Planck Institute for Solar System Research and the German Aerospace Center (DLR). The Planetary Sciences and Remote Sensing Group of FU Berlin is involved in the scientific processing and evaluation of the image data.
In Dawn’s lowest orbit, at an altitude of about 210 km, it was possible to get shoots of Vesta’s surface with a resolution of up to 20 m per pixel. Vesta’s surface was nearly completely covered by the camera in the course of the spacecraft’s one-year-long sojourn.
The combination of the Framing Camera data with that of the Visible and Infrared Spectrometer (VIR) and the Gamma Ray and Neutron Detector (GRaND) constitutes a significant basis for the understanding of the planetoids evolution. It enables insights into the early history of the solar system and thereby into that of the Earth. One of the main tasks of the research group at FU Berlin consists in developing a chronostratigraphic system. The dating of different landforms by determining the frequency distribution of crater size provides the scientists with important information to better understand the geological evolution and impact processes on Vesta. The detailed insight into meteorite impacts on Vesta makes it possible to much better establish corresponding coherences with the evolution of meteorite impacts in the young solar system. Of special interest in this case is also the examination of the material distribution of rock forming minerals and water ice. On behalf of the Dawn Science Team the researchers at FU Berlin create geologic maps and dating of Vesta’s surface.
In April 2015 the probe has arrived at Ceres, the largest body in the asteroid belt (with dimensions of 487 km x 455 km), and collected first scientific data with a resolution of about one kilometer per pixel. Currently the probe is located in the final survey orbit at an altitude of less than 400 km above the surface and takes images with a resolution of up to 30 meters per pixel.
Link to mission participation of the Planetary Sciences and Remote Sensing Group.