Development of High Precision Test Masses for the MICROSCOPE Space Project

The MICROSCOPE (MicroSatellite a trainee Compensee pour l'Observation du Principe d'Equivalence) project is an orbit-based mission to verify the Weak Equivalent Principle with an uncertainty of 10-15. To achieve this goal two differential accelerometer, each equipped with two high precision test masses (made of PtRh10 and TiAl6V4 in the form of hollow cylinders with four flats at the outer shell and six precision countersinks at each face), are to be launched in Spring 2016 and shall orbit the earth for approx. one and a half year.