Abstract The present invention provides a gravity gradiometer for 5 measuring components of the gravity gradient tensor. The gravity gradiometer comprises a housing and a gimballed support structure with at least one actuator. The gravity gradiometer further comprises at least one sensor mass arranged for movement in response to a gravity gradient. 10 The gravity gradiometer also comprises a transducer that is arranged so that the movement of the at least one sensor mass relative to a portion of the transducer generates a transducer signal. Further, the gravity gradiometer comprises an electrical feedback loop arranged 15 to direct an electrical signal to the actuator of the external support structure. The gravity gradiometer is arranged so that an influence of an external angular acceleration on the rotation of the housing is reduced by the actuator when the transducer generates a transducer 20 signal effected by the external angular acceleration on the gravity gradiometer.
