By D. Balaji, IANS,
Berlin : The US National Aeronautics and Space Administration (NASA) Thursday extended the Gravity Recovery and Climate Experiment (Grace) space mission, operated jointly with the German aerospace centre here, to 2015 from 2012.
NASA deputy administrator Lori Garver and German Aerospace Centre executive board chairman Johann-Dietrich Worner signed an agreement to extend the mission at the 100th Berlin International Air Show (ILA 2010) here.
Launched in March 2002 from Plessezk in northern Russia, the joint mission uses small satellites to produce an accurate model of the earth’s gravitational field.
“Two satellites of identical design orbit the earth 220 km apart to record local changes in the earth’s magnetism, which occur in accordance with variations and movements in the earth’s mass,” Garver told reporters here.
The German space flight control centre manages and operates the mission.
“The spacecraft fly in tandem to precisely measure the gravitational field to enable a better understanding of ocean surface currents and ocean heat transport,” Worner explained.
The mission measures changes in sea-floor pressure and shows how the mass of the oceans change. It also measures and monitors ice sheets and changes in the storage of water and snow on the continents.