"查查詞典"手機版
千萬人都在用的超大詞匯詞典翻譯APP
Syncom (for "synchronous communication satellite") started as a 1961 NASA program for active geosynchronous communication satellites, all of which were developed and manufactured by Hughes Space and Communications. Syncom 2, launched in 1963, was the world's first geosynchronous communications satellite.
詳細百科解釋