X0203 3 2009-01-29 0 0000820736 ORBITAL SCIENCES CORP /DE/ ORB 0001490183 Thompson Hollis M 21839 ATLANTIC BLVD. DULLES VA 20166 0 1 0 0 Senior VP and Controller Common Stock 22384 D Stock Option (right to buy) 12.25 2010-04-26 Common Stock 7000 D Stock Option (right to buy) 12.05 2004-05-18 2010-05-18 Common Stock 2000 D Stock Option (right to buy) 12.84 2010-05-18 Common Stock 4000 D Stock Option (right to buy) 4.00 2011-04-24 Common Stock 8500 D Stock Option (right to buy) 3.45 2011-12-04 Common Stock 10000 D Stock Option (right to buy) 5.79 2013-05-05 Common Stock 6666 D Stock Option (right to buy) 7.08 2004-06-23 2013-06-23 Common Stock 2500 D Stock Option (right to buy) 7.80 2013-06-23 Common Stock 5000 D The option became fully vested and exercisable as of January 20, 2002. The option became fully vested and exercisable as of October 26, 2005. The option became fully vested and exercisable as of February 6, 2003. The option became fully vested and exercisable as of December 4, 2003. The option became fully vested and exercisable as of May 15, 2006. The option became fully vested and exercisable as of June 23, 2006. /s/ Hollis M. Thompson by Vanessa T. Hoang, Attorney-in-Fact 2010-04-29