Orbital Sciences Corporation : Orbital Sciences Corporation : ORBITAL'S OBV ROCKET SUCCESSFULLY LAUNCHED FOR MISSILE DEFENSE

 Orbital Sciences Corporation : Orbital Sciences Corporation : ORBITAL'S OBV
   ROCKET SUCCESSFULLY LAUNCHED FOR MISSILE DEFENSE INTERCEPTOR SYSTEM TEST

For Immediate Release                                        
 
For More Information Contact:

Barron Beneski (703) 406-5528
Public and Investor Relations
beneski.barron@orbital.com

  ORBITAL'S OBV ROCKET SUCCESSFULLY LAUNCHED FOR MISSILE DEFENSE INTERCEPTOR
                                 SYSTEM TEST

  -- Company's Long-Range Silo-Launched Booster Completes 11^th Consecutive
       Successful Flight for the Ground-Based Missile Defense System --

(Dulles, VA  28  January 2013)  -  Orbital Sciences  Corporation  (NYSE:  ORB) 
announced today that its Orbital Booster  Vehicle (OBV), which is the  booster 
rocket for the  Ground-Based Interceptor (GBI),  was successfully launched  as 
part of a test of the  Ground-Based Midcourse Defense (GMD) program.   Orbital 
provides the OBV as part of an industry team led by The Boeing Company  (NYSE: 
BA) for the  U.S. Missile  Defense Agency (MDA).   The OBV  was launched  from 
Vandenberg Air Force Base,  CA on Saturday,  January 26, 2013  as part of  the 
test designated as  CTV-01.  Following its  launch from a  silo, the OBV  flew 
downrange over the Pacific Ocean  and successfully deployed an  Exoatmospheric 
Kill Vehicle (EKV).

The test began at 2:00 p.m. (PST) when an OBV ground-based interceptor  lifted 
off from Vandenberg Air Force Base.   The GBI, which included a modified  EKV, 
measured performance data of the EKV as it operated under conditions  designed 
to stress  its  design.  Data  gathered  from today's  test  will be  used  to 
validate the modified EKV design.

Following a preliminary post-flight  analysis of the  data collected from  the 
mission, MDA and the  GMD team confirmed that  all primary OBV objectives  for 
CTV-01 were achieved.  These included pre-launch built-in test  functionality, 
silo launch  and  fly  out of  the  OBV,  accurate delivery  of  the  EKV  and 
acquisition of telemetry data for further characterization of the OBV's flight
characteristics.  Orbital developed the OBV  under a multi-year contract  from 
Boeing that began  in 2002.  The  OBV and the  EKV make up  the GBI, which  is 
assembled by Boeing.

"The CTV-01 test  marks the  eleventh successful  flight of  our OBV  booster, 
supporting MDA's  ongoing testing  of the  GMD system,"  said Mr.  Ron  Grabe, 
Orbital's Executive Vice President and  General Manager of its Launch  Systems 
Group.  "Orbital is extremely proud to be a part of this program that provides
the only  defensive capability  for our  homeland against  long-range  missile 
attack, and we are particularly proud of the flight test successes achieved by
the OBV."

Orbital's space  launch vehicles,  missile  defense interceptors  and  related 
suborbital rockets are  primarily produced  at the  company's engineering  and 
manufacturing  facility  in  Chandler,  AZ   and  its  vehicle  assembly   and 
integration facilities at Vandenberg  Air Force Base,  CA and Huntsville,  AL. 
 The company's launch vehicles are used by commercial and government customers
to deliver satellites to  low altitude orbits above  the Earth and in  missile 
defense systems, both as threat-stimulating target vehicles and as interceptor
boosters for U.S. national defense systems.
  
In addition to its  launch vehicle systems,  Orbital's other primary  products 
are satellites and related space systems,  which are also used by  commercial, 
civil government and  military customers.  These  products include  low-orbit, 
geostationary-orbit  and  planetary  spacecraft  for  communications,   remote 
sensing, scientific and defense  missions.  Orbital also provides  human-rated 
space systems for Earth-orbit, lunar and other missions, as well as  satellite 
subsystems and  space-related technical  services to  government agencies  and 
laboratories.

More information  about Orbital  can be  found at  http://www.orbital.com  and 
follow us on Twitter @OrbitalSciences.

                                    # # #

Approved for Public Release      
13-MDA-7153 (27 January 13)

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Source: Orbital Sciences Corporation via Thomson Reuters ONE
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