jgg     2002 22 (1):  1-5    ISSN: 0412-1961  CN: 21-1139/TG THE SATELLITE GRAVITY SURVEYING TECHNOLOGYAND RESEARCH OF EARTH'S GRAVITY Ning Jinsheng The Key Laboratory of Geo-spa6e Environment and Geodesy，Ministry of education, Wuhan University，W uhan 430079 Received: 1900-01-01  Revised: 1900-01-01  Online: null Supporting info null