In this photo, taken April 29, 2011, technicians install lifting brackets prior to hoisting the 200-kilogram (440-pound) GRAIL-A spacecraft out of vacuum chamber after testing.

In this photo, taken April 29, 2011, technicians install lifting brackets prior to hoisting the 200-kilogram (440-pound) GRAIL-A spacecraft out of vacuum chamber after testing. Along with its twin GRAIL-B, the GRAIL-A spacecraft underwent an 11-day-long test at Lockheed Martin Space Systems in Denver that simulated many of the flight activities they will perform during the mission, all while being exposed to the vacuum and extreme hot and cold that simulate space.

For more information about GRAIL, please visit http://solarsystem.nasa.gov/grail.

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