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Analysis at the SGF

The SGF is an ILRS Analysis Centre and performs regular data analysis of the other geodetic techniques.


The SGF consistently provides high quality data to support geodetic and geophysical science. On-site analysis programs use this data along with data and outputs from mathematical models available from other sites and institutions.

SLR analysis using a software package developed on site called SATAN produces a global solution using all the laser range observations from the Lageos or Etalon satellites made by the global ILRS network. The SGF is an ILRS Analysis Centre and contributes to a combined SLR solution for inclusion in the definition of the International Terrestrial Reference Frame (ITRF).

GNSS analysis with the GPS software package GAMIT produces daily co-ordinates of the GNSS sites at the SGF, HERS and HERT, using a global network of other GNSS sites and pre-determined IGS final orbits, absolute antenna phase centre offsets and Earth orientation parameters. GAMIT is also used to calculate highly precise short baselines between the GNSS sites at the SGF.

The absolute gravimeter is routinely run every Wednesday and this data time series is analysed on-site. The results are, for example, impacted by Earth tides, ocean loading, earthquakes, Atlantic storms, local hydrological variations and local height change.