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How do you summarize the mission of a spacecraft that has traversed the solar system for exactly eleven years?
For Dawn, the Jet Propulsion Laboratory (JPL) in Pasadena, California, Dawn was primarily a first mission.
"This was the first time that a space probe was visiting Ceres, it was the first time that a space probe was visiting Vesta – and we were able to study the two asteroids with the same spacecraft and the same instruments! compare the two celestial bodies. "
The small planet Vesta was explored by Dawn for a year (DLR)
The Dawn spacecraft had orbited Vesta for a year in 2011 before leaving for the dwarf planet Ceres Both proved to be opposite in the asteroid belt.
"Ceres has water ice and hydrated minerals. This Ceres is a representative of rather wet objects in the asteroid belt. Vesta, on the other hand, is dry, with solidified lava flows. We learned a lot by comparing these different celestial bodies. "
Hi Patches of Salt
For example, astronomers have learned that Ceres does not have a liquid ocean of salt water under the surface, which should now freeze Because Ceres did not no atmosphere, no liquid water can stand in the vacuum on its surface, it sublimes immediately, so it goes from solid state – frozen ice – in the gaseous state. salt deposits on or just under the surface.
"We are still trying to find out if the shiny surfaces of salt in the Occator crater have been made visible by the impact of an asteroid or there are internal processes such as Bring salt deposits to the surface. "[19659002] 
A NASA spacecraft" Dawn "photographs the Occator crater on the planetary dwarf" Ceres. "(1945-19006)
Now Astronomers Knowing what these mysterious white spots on Ceres have been for a long time, they were able to relate them to other objects in the solar system.
" C & It's the first time we've discovered such bright spots on a celestial body, but that does not mean that they're unique – it's probably just because we visited for the first time a dwarf planet of the species Ceres. "
Meanwhile, researchers are targeting another object with the asteroid Hygiea whose surface spectrum is similar to that of Ceres.
Uncertainties also exist in the organic compounds that Dawn detected in a crater at the North Pole.
"For the moment, we are not sure if the chosen asteroid has brought these organic compounds"
Eternal Calm in the cemetery ash tree
Dawn's approach to Ceres only 35 kilometers each turn, while the orbit of the probe moves a little to the south each time that it revolves around Ceres. These days, Uvara, another crater in Dawn's home, is several hundred kilometers in diameter and is therefore more than twice as big as the crater of the Occador, Carol Raymond, chief scientist of the mission, also explains JPL.
"Uvara has a sort of ridge in the middle. There, the material seems to be accumulated after an asteroid impact. Uvara will become the last crater of Dawn, probably in September, the probe will be short of rocket propellant without hydrazine, without attitude control, without orientation in the space. plus, then Dawn will become an artificial moon of Ceres.
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