This image from NASA’s Dawn spacecraft shows part of Messor Crater (25 miles or 40 kilometres, wide), located at northern mid-latitudes on Ceres. The scene shows an older crater in which a large lobe-shaped flow partly covers the northern (top) part of the crater floor. The flow is a mass of material ejected when a younger crater formed just north of the rim. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.Features on dwarf planet Ceres that piqued the interest of scientists throughout 2015 stand out in exquisite detail in the latest images from NASA’s Dawn spacecraft, which recently reached its lowest-ever altitude at Ceres. Dawn took these images near its current altitude of 240 miles (385 kilometres) between 19 and 23 December 2015.
Kupalo Crater, one of the youngest craters on Ceres, shows off many fascinating attributes at the high image resolution of 120 feet (35 metres) per pixel. The crater has bright material exposed on its rim, which could be salts, and its flat floor likely formed from impact melt and debris. Researchers will be looking closely at whether this material is related to the “bright spots” of Occator Crater. Kupalo, which measures 16 miles (26 kilometres) across and is located at southern mid-latitudes, is named for the Slavic god of vegetation and harvest.This image from NASA’s Dawn spacecraft shows Kupalo Crater, one of the youngest craters on Ceres. The crater has bright material exposed on its rim and walls, which could be salts. Its flat floor likely formed from impact melt and debris. Kupalo, which measures 16 miles (26 kilometres) across and is located at southern mid-latitudes, is named for the Slavic god of vegetation and harvest. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.“This crater and its recently-formed deposits will be a prime target of study for the team as Dawn continues to explore Ceres in its final mapping phase,” said Paul Schenk, a Dawn science team member at the Lunar and Planetary Institute, Houston.
Dawn’s low vantage point also captured the dense network of fractures on the floor of 78-mile-wide (126-kilometre-wide) Dantu Crater. One of the youngest large craters on Earth’s moon, called Tycho, has similar fractures. This cracking may have resulted from the cooling of impact melt, or when the crater floor was uplifted after the crater formed.The fractured floor of Dantu Crater on Ceres is seen in this image from NASA’s Dawn spacecraft. Similar fractures are seen in Tycho, one of the youngest large craters on Earth’s Moon. This cracking may have resulted from the cooling of impact melt, or when the crater floor was uplifted after the crater formed. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.A 20-mile (32-kilometre) crater west of Dantu is covered in steep slopes, called scarps, and ridges. These features likely formed when the crater partly collapsed during the formation process. The curvilinear nature of the scarps resembles those on the floor of Rheasilvia, the giant impact crater on protoplanet Vesta, which Dawn orbited from 2011 to 2012.
Dawn’s other instruments also began studying Ceres intensively in mid-December. The visible and infrared mapping spectrometer is examining how various wavelengths of light are reflected by Ceres, which will help identify minerals present on its surface.
Dawn’s gamma ray and neutron detector (GRaND) is also keeping scientists busy. Data from GRaND help researchers understand the abundances of elements in Ceres’ surface, along with details of the dwarf planet’s composition that hold important clues about how it evolved.NASA’s Dawn spacecraft viewed this Cerean crater, which is covered in ridges and steep slopes, called scarps on 23 December 2015. These features likely resulted when the crater partly collapsed during its formation. The curvilinear nature of the scarps resembles those on the floor of Rheasilvia, the giant impact crater on Vesta, which Dawn orbited from 2011 to 2012. The 20-mile-wide (32-kilometre-wide) crater is located just west of the larger, named crater Dantu, at northern mid-latitudes on Ceres. Both of these impact features were captured during Dawn’s Survey orbit. Image credit: NASA/JPL-Caltech/UCLA/MPS/DLR/IDA.The spacecraft will remain at its current altitude for the rest of its mission, and indefinitely afterward. The end of the prime mission will be 30 June 2016.
“When we set sail for Ceres upon completing our Vesta exploration, we expected to be surprised by what we found on our next stop. Ceres did not disappoint,” said Chris Russell, principal investigator for the Dawn mission, based at the University of California, Los Angeles. “Everywhere we look in these new low-altitude observations, we see amazing landforms that speak to the unique character of this most amazing world.”
NASA’s Dawn spacecraft is in the process of dropping into its final, lowest-ever orbit around the dwarf planet Ceres, allowing it to make repeated passes within 50 kilometres (30 miles) of the surface.
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