## Preprocessing of satellite gravity gradient of GOCE mission

GOCE satellite was launched in 2009 on a low (260 km) orbit and it contains the electrostatic gravity gradiometer which is destining for measuring of gravity gradients. In the paper the algorithm of using of quaternions during the transformation of gravity gradients from the system GRF (Gradiometer Reference Frame) to LNOF (Local North Oriented Frame) is shown. Mathematical verification of intermediate calculations is realized and methods of improvement of data using are shown.