ONERA accelerometers for future gravity mission

The 2017-2027 Decadal Survey for Earth Science and Applications from Space has identified the Targeted Mass Change Observable as one of 5 Designated Mission. In Europe, ESA has confirmed at Ministerial Counsel of November 2022 to continue the development on the Next Generation Gravity Mission with a Phase B. These missions will continue the observation provided by GRACE and GRACE-FO. In these missions and the future concepts, the accelerometer provides either the gravity signal in a gradiometer configuration (GOCE type mission), or the non-gravitational acceleration to be suppressed to the ranging measurement between two satellites (GRACE-type mission). ONERA has procured the accelerometer for all the previous gravity missions (GRACE, GOCE, GRACE-FO) and works to improve the scientific return of the instruments for the future missions. In a frame of a contract with ESA, ONERA is developing its new accelerometer MicroSTAR, a high accuracy accelerometer with 3 sensitive linear acceleration measurements as well as 3 angular acceleration measurements for the attitude control or reconstruction. In parallel, a miniaturized version of MicroSTAR with low accuracy, CubeSTAR accelerometer, is developed with internal funding. CubeSTAR is adapted for constellation or nanosat. Another way is to improve the low-frequency noise of the accelerometer, by hybridization of electrostatic accelerometer with cold atom interferometer. The presentation will detail these developments.