The first products based on GOCE satellite data are now available online through ESA's Earth observation user services tools. ESA launched the satellite in March 2009 on a mission to map Earth's gravity with unprecedented accuracy and spatial resolution.
The final gravity map and model of the geoid based on GOCE data will provide users with well-defined products that will be instrumental in advancing science and applications in a broad range of disciplines. However, there are a number of steps that have to be taken in order to turn the raw data into suitable products for users.
Raw data are downlinked from GOCE to the ground stations in Kiruna, northern Sweden, and on Svalbard, Norway. They are immediately forwarded to the Flight Operations Segment at ESA's European Space Operations Centre (ESOC) in Darmstadt, Germany, which then links them through to the Payload Data Ground Segment at ESA's European Space Research Institute (ESRIN) in Frascati, Italy. Here, through a process of calibration and validation, the data undergo an important transformation from telemetry to 'level-1b' data products.
Level-1b products are the time series of converted, calibrated and validated measurements taken by GOCE. They consist mainly of the gravity gradients in the instrument reference system and the orbit data (satellite-to-satellite tracking observations, positions and velocity) in an Earth-fixed coordinate system.
In addition, satellite data such as the attitude of the spacecraft and other housekeeping data complete the level-1b data.
These level-1b data, covering the period 1-30 November 2009, are available free of charge to scientific and non-commercial users, and much more will come in the following weeks and months.
"After an intensive calibration and validation phase, we are all very happy to see the science community at large getting involved in the exploitation of the data," ESA GOCE Mission Manager Rune Flo
|Contact: Robert Meisner|
European Space Agency