AbstractThe Gravity Probe B (GP-B) Relativity Mission is a fundamental physics experiment to test Einstein’s theory of General Relativity based on observations of spinning gyroscopes onboard a satellite in a near-polar, near-circular orbit at an altitude of about 640km around the Earth. The GP-B mission was designed to test two predictions of Einstein’s theory, the geodetic effect and the frame-dragging effect, to an accuracy better than 5×10−4arcsec/yr. Drag-free control technology is implemented in the GP-B translation control system to minimize support forces and support induced torques on the gyroscopes. A Global Positioning System (GPS) receiver onboard the GP-B satellite provides real-time position, velocity and timing data. The GP-B orbit is determined on the ground based on the 3-axis GPS position data and verified independently with ground-based laser ranging measurements. This paper describes the design and implementation of the drag-free translation control and orbit determination system of the GP-B satellite. The on-orbit performance of the drag-free translation control system satisfies the requirements of the GP-B science experiment. The residual accelerations from the gyroscope control efforts are less than 4×10−11m/s2 (along the satellite roll axis) and less than 2×10−10m/s2 (transverse to the satellite roll axis) between 0.01mHz and 10mHz in inertial space. The non-gravitational acceleration along the satellite roll axis, including a nearly constant component (which is kept below 1×10−7m/s2) and a sinusoidal component (whose amplitude varies from about 5×10−7m/s2 to less than 1×10−8m/s2), causes the gyroscope spin axis to drift less than 9×10−5arcsec/yr. The orbit determination system is found to provide overlapping orbit solution segments having RMS (root mean square) position and velocity errors of a few meters and a few mm/s, well within the RMS mission requirements of 25m and 7.5cm/s.


    Access

    Check access

    Check availability in my library

    Order at Subito €


    Export, share and cite



    Title :

    On-orbit performance of Gravity Probe B drag-free translation control and orbit determination


    Contributors:
    Li, J. (author) / Bencze, W.J. (author) / DeBra, D.B. (author) / Hanuschak, G. (author) / Holmes, T. (author) / Keiser, G.M. (author) / Mester, J. (author) / Shestople, P. (author) / Small, H. (author)

    Published in:

    Publication date :

    2007-03-06


    Size :

    10 pages




    Type of media :

    Article (Journal)


    Type of material :

    Electronic Resource


    Language :

    English





    On-Orbit Performance of the Gravity Probe B Drag-Free Translation Control System (AAS 06-083)

    Bencze, W. J. / DeBra, D. B. / Herman, L. et al. | British Library Conference Proceedings | 2006


    Orbit and formation control for low-earth-orbit gravimetry drag-free satellites

    Canuto, Enrico / Colangelo, Luigi / Buonocore, Marcello et al. | Tema Archive | 2015


    Orbit and formation control for low-earth-orbit gravimetry drag-free satellites

    Canuto, Enrico / Colangelo, Luigi / Buonocore, Marcello et al. | SAGE Publications | 2015