News Releases

april 2008

GOCE, a space mission exploring terrestrial gravity

The Goce [ESA] satellite is officially ready for its departure. Its mission will be to accurately measure the gravity on the surface of our globe - extreme measurements but within the capabilities of the Onera's ultra-sensitive accelerometers.

On 4th April 2008 at Noordwijk (Netherlands), ESA presented the GOCE mission (pronounced gotchay) to the press. The purpose of the mission is to determine and very accurately map the Earth's gravity field. The satellite Prime Contarctor is Thales Alenia Space and Onera is supplying the key measuring instruments: 6 ultra-sensitive accelerometers. These instruments, with a resolution of 2.10-12 ms-2/Hz1/2 , form the essential part of the gradiometer, used to measure, in low orbit, the local components of the gravity gradient.

The mission scientific customer is the "MAG", or Mission Advisory Group, made up of twenty European scientists who are experts in geodesy, gravimetry and geophysics. Onera and Pierre Touboul, of the Instrumentation and Sensing Department, are participating, in partnership with the MAG chairman, Reiner Rummel of the University of Munich.

The results obtained during the twenty months that this mission is expected to last will be used by geophysicists to refine our knowledge of the geoid (a surface close to the real form of the Earth taking into account the variations in the planet's density) with geodetic applications. Oceanographers will be able to deduce models of oceanic circulation. The Earth's gravitational signature will also provide accurate data for a new understanding of Earth’s interior and polar ice sheets behaviour.

The launch of the GOCE satellite, initially planned for May 2008, had been delayed a first time until September 2008 due to the failure of a Proton launcher at Baikonour on 15th March, ,then a second time until beginning of 2009 after the investigation of a failure in the guidance and navigation system of the launcher's Upper Stage (Breeze KM). A Rockot launcher will put it into orbit in March 2009, from the Plessetsk base in northern Russia.

 

Last Update: 8 January, 2009 - © ONERA 2009 - Terms of use