Proposed to CNES by ONERA and the OCA, the MICROSCOPE mission will allow in late 2014 a test of the Equivalence Principle with a precision of 10-15. After DEMETER and PARASOL, MICROSCOPE is the third mission of the microsatellite program MYRIADE. The weak equivalence principle, or universality of free fall, states :
This theory has been tested using numerous methods (torsion balances, laser ranging etc.), but the noise and vibrations inherent in any Earth-bound test environment limit the accuracy to less than 10-13. New physics theories such as string theory or supergravity propose a possible EP violation under 10-13 : the need to go below this level shows the significance of the mission which uses as a test environment space, in a drag-free satellite.
NB: This site contains excerpts from articles published by the Microscope team.