Satellite test of the equivalence principle: Overview and progress

摘要

STEP, the Satellite Test of the Equivalence Principle, is reviewed and the current status of the project is discussed. This space- based experiment will test the universality of free fall and is designed to advance the present state of knowledge by over five orders of magnitude. The international STEP collaboration is pursuing a development plan to improve and verify the technology readiness of key systems. We discuss recent advances with an emphasis on accelerometer fabrication and tests. Critical technologies successfully demonstrated in flight by the Gravity Probe B mission also contribute to progress.