The Orbital ATK Cygnus spacecraft sits on top of an Atlas V rocket ready for launch to the International Space Station. The mission is set to lift off on Tuesday, March 22, from Space Launch Complex 41 at Cape Canaveral Air Force Station in Florida. The 30 minute launch window opens at 11:05 p.m. EDT. Today’s L-1 forecast shows a 90 percent chance of favorable weather conditions for launch. NASA TV coverage of the event begins at 10 p.m.