The GRACE twin satellites, launched 17 March 2002, are making detailed measurements of Earth's gravity field and revolutionizing investigations about Earth's water reservoirs, over land, ice and oceans.
GRACE is a collaboration of the US and German space agencies (NASA and DLR). GRACE ground segment operations are currently co-funded by GFZ German Research Centre for Geosciences and the European Space Agency (ESA). NASA, ESA, GFZ and DLR are supporting the continuation of the measurements of mass redistribution in the Earth system.The key partners in the design, construction and launch of the mission have been the Jet Propulsion Laboratory, the University of Texas Center for Space Research, GFZ German Research Centre for Geosciences, as well as Astrium GmBH, Space Systems Loral (SS/L), Onera and Eurockot GmBH.
GRACE TELLUS provides user-friendly data grids, with most corrections applied, to analyze changes in the mass of the Earth's hydrologic components. We do so by using GRACE mission data, with additional post-processing, alone or in combination with other data, to generate gridded products (monthly and time-averaged) with the most up-to-date corrections.
GRACE Data in spherical harmonic form, for both the time-averaged and time-variable fields, are available from either PO.DAAC or GFZ.
Other sources of derived GRACE products are listed in the left bar under 'Partners and Related Sites'.
MORE INFORMATION: The NASA GRACE Fact Sheet (PDF, 136 KB) has basic information about gravity, about the science of measuring the gravity field, and about GRACE instruments. The GRACE Launch Press Kit (PDF, 226 KB) was prepared to explain the GRACE mission and science to journalists before launch in 2002, and it contains details on the spacecraft dimensions, mass, power, etc.
ACKNOWLEDGEMENTS: GRACE Tellus was supported by the NASA Research, Education, and Applications Solution Network (REASON), and is now supported by NASA's 'Making Earth System Data Records for Use in Research Environments' (MEASURES) Program. We are grateful to NASA's Dr. Martha Maiden for her continued support. GRACE Tellus is a member of the Earth Science Information Partner (ESIP) Federation.
Why GRACE Tellus ? . Tellus was the Roman Goddess of the planet Earth, and in English it offers a wordplay, so we can ask 'What can GRACE, and time changes in gravitational acceleration TELL US about our changing planet'?
For any problems or suggestions, please contact victor.zlotnicki at jpl.nasa.gov
LAST UPDATE: 20130319 V.Zlotnicki
Contributors: A.Thevenin, A. Hayashi, DPC, M. Srinivasan.