在各类侦察卫星中,照相侦察卫星发展最早,发射数量最多,是空间侦察、监视的主要力量。照相侦察卫星原本只为美国和前苏联所拥有,在冷战铁幕下,通过它互相窥探军事机密。时至今日,照相侦察卫星又有了新的发展:实时传输型照相侦察卫星已经成为照相 Among various reconnaissance satellites, photographic reconnaissance satellites have the earliest development and the largest number of launches. They are the major force in space reconnaissance and surveillance. Photographic reconnaissance satellites were originally only owned by the United States and the former Soviet Union and were used to reveal military secrets to each other under the Cold War iron curtain. To date, new developments have taken place in photographic reconnaissance satellites: real-time transmission photographic reconnaissance satellites have become photographic