10 September 2018
Animation: Flight over Occator crater
At a resolution of five metres per pixel and a recording altitude of just 32 kilometres, onlookers are able to fly over Ceres, enjoying a perfect view of Occator’s unusual topography and the bright deposits in its interior. The bright, reflective regions have now been given their own names: the particularly striking region at the heart of Occator, with light spots and a fissured bulge at its centre, has been named 'Cerealia Facula', while the slightly less reflective patches to the east are called 'Vinalia Faculae'.
NASA/JPL-Caltech/UCLA/MPS/DLR/IDA ESO/S. Brunier.
Over the next few weeks, the Dawn asteroid mission will run out of the fuel required for attitude control. The spacecraft will orbit around the small planet Ceres in the asteroid belt for decades, although it will be impossible for the researchers to stay in contact with it. But before that happens, the scientists are once more presenting significantly improved mapping of the largest object in the asteroid belt thanks to the German camera system on board – as is particularly apparent in the example of the biggest crater, Occator. “In the past year, by means of an elliptical orbit which brings Dawn as close as 35 kilometres above the surface, we have been able to acquire images of up to three metres per pixel,” states planetary scientist and camera-team member of the NASA Dawn mission Ralf Jaumann, from the German Aerospace Center (Deutsches Zentrum für Luft- und Raumfahrt; DLR), where the image data for the elevation model were processed. “This has provided us with image data that is almost 10 times more accurate – a fantastic success before the end of the mission."
Up to now, the highest resolution image data – at 32 metres per pixel – originated from the so-called Low Altitude Mapping Orbit (LAMO), with a flight altitude of 370 kilometres. Since July 2017, Dawn has been in the Extended Mission Phase 2 (XM2), in which the researchers directed the space probe from a circular to an elliptical orbit. This allows the probe an extremely close approach on one side of the orbit, corresponding to just three times the altitude of a passenger jet. This is made possible by the lack of atmosphere on Ceres. The animation that has now been released shows a preliminary high-resolution image mosaic of the enormous impact crater Occator at approximately five metres per pixel from XM2 data as compared with the previously recorded LAMO data. The video was produced using more than 1000 images acquired by the German Framing camera, more than 600 stereo combinations and 1.8 billion calculated points on the surface, which the researchers from the DLR Institute of Planetary Research in Berlin used to create a three-dimensional elevation model.
The Dawn mission is drawing to an end after more than 10 years of ground-breaking planetary research, breathtaking images, and unprecedented accomplishments in spacecraft engineering. The mission has already been extended several times and has thereby exceeded the expectations of the scientists in the exploration of the celestial bodies Ceres and Vesta, which account for 45 percent of the mass of the asteroid belt between Mars and Jupiter. Now, the space probe is running out of hydrazine. When this happens, which will most likely be between September and October, Dawn will lose its ability to communicate with Earth, remaining in silent orbit around Ceres.
The Dawn mission is managed by NASA's Jet Propulsion Laboratory (JPL) in Pasadena, which is a division of the California Institute of Technology. The University of California, Los Angeles, is responsible for overall Dawn mission science. The Framing Camera system on the spacecraft was developed and built under the leadership of the Max Planck Institute for Solar System Research in Göttingen, Germany, in collaboration with the DLR Institute of Planetary Research in Berlin and the Institute of Computer and Communication Network Engineering in Braunschweig. The Framing Camera project is funded by the Max Planck Society, DLR, and NASA/JPL.
Last modified:14/09/2018 13:12:17