今年5月15日苏联试验成功大型通用运载火箭“能源”号。这种两级运载火箭的发射重为2000多吨,能把100多吨的有效载荷送入轨道,可将航天飞机和大型航天器送入绕地球轨道。目前美国也正研制一种大型运载火箭,准备在90年代中期使用。它能运载136吨的有效载荷,到达1000公里的圆形极轨道。 On May 15 this year, the Soviet Union successfully tested a large-scale universal launch vehicle “Energy”. The launch of this two-stage launch vehicle, weighing over 2,000 tons, can bring more than 100 tons of payload into orbit and can send space shuttles and large spacecraft around orbit. At present, the United States is also developing a large launch vehicle to be used in the mid-1990s. It can carry 136 tons of payload to reach 1,000 kilometers of circular polar orbit.