Inside a clean room in Building 1555 at Vandenberg Air Force Base in California, technicians install the first half of the Northrop Grumman Pegasus XL payload fairing around NASA's Ionospheric Connection Explorer (ICON) on Oct. 4, 2018. ICON is being prepared for its launch on the Pegasus XL, which is attached to the company's L-1011 Stargazer aircraft, from the Skid Strip at Cape Canaveral Air Force Station in Florida. Launch is scheduled for Oct. 26. ICON will study the frontier of space - the dynamic zone high in Earth's atmosphere where terrestrial weather from below meets space weather above. The explorer will help determine the physics of Earth's space environment and pave the way for mitigating its effects on our technology, communications systems and society.