Launch alert! We are excited to announce that we are targeting Sunday, May 20 for the launch of our #OA9 mission to @Space_Station. The 5-minute launch window will open at 5:04 a.m. EDT. Learn more here: https://t.co/dBDd191faj pic.twitter.com/dDKMrnukpf

— Orbital ATK (@OrbitalATK) April 24, 2018