October 22, 2013
ESA’s GOCE Gravity Explorer Mission Draws To A Close
Lee Rannals for redOrbit.com - Your Universe Online
The European Space Agency (ESA) announced on Monday its Gravity Field and Steady-State Ocean Circulation Explorer (GOCE) mission has come to an end.
ESA said that after mapping the Earth's gravity for four years the satellite has finally run out of fuel, effectively ending the mission. GOCE's gradiometer instrument was the first of its kind in space and it helped to map variations in Earth's gravity with unrivaled precision.
GOCE has also helped to provide dynamic topography and circulation patterns of the oceans with unprecedented quality and resolution. This mission helped improve scientific understanding of the dynamics of world oceans.
“This innovative mission has been a challenge for the entire team involved: from building the first gradiometer for space to maintaining such a low orbit in constant free-fall, to lowering the orbit even further,” said Volker Liebig, ESA’s Director of Earth Observation Programs.
“The outcome is fantastic. We have obtained the most accurate gravity data ever available to scientists. This alone proves that GOCE was worth the effort – and new scientific results are emerging constantly.”
GOCE became the first seismometer in orbit when it detected sound waves from the massive earthquake that hit Japan on March 11, 2011. Although the palmed mission was completed in April, 2011, fuel consumption was much lower than anticipated because of low solar activity, allowing researchers to continue using the orbiting workshop beyond the original time frame.
ESA said GOCE ran out of natural gas on October 21, but data acquisition and satellite operations can still function for two more weeks. The satellite is expected to reenter Earth's atmosphere in about two weeks, after which it will end activities for the GOCE flight control team.
Most of the GOCE satellite will disintegrate when it enters the Earth's atmosphere, but some of the smaller parts will likely reach Earth's surface. ESA said it cannot predict when and where these parts land, but the affected area will be narrowed down closer to the time of reentry.
The Inter-Agency Space Debris Coordination Committee will be monitoring the descent along with ESA's Space Debris Office. ESA said it would be keeping Member States and authorities aware of where the debris might hit. The danger to life and property is very low as about two-thirds of the Earth is covered by oceans and vast areas that are sparsely populated