Orbital Schedules New Antares Rocket Launch Window

A-1 Mission Team Working Toward an Attempt on Saturday, April 20

(Dulles, VA 18 April 2013) Orbital Sciences Corporation (NYSE: ORB), one of the world’s leading space technology companies, today announced that the next launch attempt for the new Antares rocket will be no earlier than Saturday, April 20, at 5 p.m. The mission management team met this afternoon to evaluate weather forecasts and optimum crew work schedules to provide two back-to-back opportunities for a launch attempt.

Weather conditions deteriorate on Friday, April 19, but improve significantly over the next two days increasing the chances for acceptable conditions at launch time. This also allows the Antares launch team a day of rest before back-to-back opportunities on Saturday, April 20 and Sunday, April 21.