September 15, 1991 (, Xinwei August eighth day), the largest man-made satellite into space.

1991 9 15 U.S. "Discovery" space shuttle astronauts in space successfully released a high-altitude atmospheric exploration satellite. It weighs 6.6 tons, valued at $ 740 million. It is said that this is the largest satellite in the release so far.
According to foreign reports, the satellite will run in a high-altitude orbit 570 kilometers above the ground a year and a half destruction observation pollution and the ozone layer of the Earth's atmosphere. It is a satellite of the United States to the first one for the systematic and detailed study of the fragile ozone layer. Fengyun
exploration satellite is the first satellite launch by NASA as "Planet Earth Plan. "Planet Earth Plan is a long-term plan to study the Earth's environment, its purpose is to study the pollution of the atmosphere and the impact of human activities on the biosphere. (L $ dj��.c��m)