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Juling Crater oblique view

Juling Crater oblique view
Juling Crater oblique view Dawn took this picture of Juling Crater in LAMO from an altitude of 240 miles (385 kilometers) on April 30, 2016. When we presented a different view of Juling, taken four months later, we described the surprising discovery of ice there. In October 2016, in XMO2, Dawn successfully accomplished the challenging assignment of acquiring infrared spectra of Juling's north wall, where the ice had been spotted, at three different times of the Cerean day. Comparing these five observations, scientists have determined that the area of ice increased from 1.4 square miles (3.6 square kilometers) to 2.1 square miles (5.5 square kilometers). In other words, the ice grew by 470 acres (190 hectares) over those six months. This is the first detection of a change on Ceres during Dawn's exploration. Scientists attribute the change to a seasonal cycle of solar heating of the crater floor. During that period, late in southern hemisphere winter, the Sun was moving south (toward Juling, which is at 36°S). As the ground warmed, it released water vapor. The vapor then condensed on the colder north wall of the crater, which faces away from the Sun. The crater wall acts as a "cold trap," collecting ice. Full image and caption. NASA / JPL-Caltech / UCLA / MPS / DLR / IDA