The Northrop Grumman Pegasus XL rocket, with NASA's Ionospheric Connection Explorer (ICON) secured in its payload fairing, rolls out from Building 1555 to the runway at Vandenberg Air Force Base in California on Sept. 25, 2019. The Pegasus XL rocket will be attached beneath the company's L-1011 Stargazer aircraft for the flight to Cape Canaveral Air Force Station (CCAFS) in Florida. ICON will launch from the Skid Strip at CCAFS in Florida. Launch is scheduled for Oct. 10, 2019. 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 and communications systems.