'Dawn' of the historic asteroid belt mission:

Dawn missed scheduled communications sessions with NASA's Deep Space Network on October 31 and November 1. After the flight team eliminated other possible causes for the missed communications, mission managers concluded that the spacecraft finally ran out of hydrazine, the fuel which keeps the spacecraft oriented and in communication with Earth, NASA said in a statement late on Thursday.

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About Dawn spacecraft:

The Dawn spacecraft launched 11 years ago to visit the two largest objects in the main asteroid belt. Currently, it's in orbit around the dwarf planet Ceres, where it will remain for decades. Launched in 2007, Dawn accomplished a journey propelled by ion engines that put about 4.3 billion miles (6.9 billion km) on its odometer. In 2015, Dawn became the first to visit a dwarf planet and go into orbit around two destinations beyond Earth.

Dawn's contribution to space exploration:

The demands we put on Dawn were tremendous, but it met the challenge every time. It's hard to say goodbye to this amazing spaceship, but it's time," said Marc Rayman, Mission Director and Chief Engineer at NASA's Jet Propulsion Laboratory (JPL).

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"The astounding images and data that Dawn collected from Vesta and Ceres are critical to understanding the history and evolution of our solar system," Zurbuchen said.