#TBT: NASA Launches Multi-instrumented, Earth-Observing Satellite -- Sept. 12, 1991 This week in 1991, STS-48 launched aboard space shuttle Discovery to deploy the Upper Atmosphere Research Satellite -- the first multi-instrumented satellite to observe numerous chemical components of Earth's atmosphere for better understanding of photochemistry. NASA's fleet of satellites, its airborne missions and researchers address some of the critical challenges facing our planet today and in the future -- climate change, sea level rise, freshwater resources and extreme weather events. Credit: NASA/MSFC #sts48 #nasa #satellite #launch #atmoshphere #throwback #discovery