REDONDO BEACH, Calif., Feb. 18, 2009 -- A primary operational and science instrument for the National Polar-orbiting Operational Environmental Satellite System (NPOESS) has passed a key environmental test at Northrop Grumman Corporation's (NYSE:NOC) subcontractor, Raytheon Company. NPOESS is the nation's next generation low Earth orbiting weather and climate monitoring system, which will provide timely and essential data to civilian and military users through 2025.

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Vibration testing of the first Visible Infrared Imager Radiometer Suite (VIIRS) flight unit, including both the OptoMechanical Module and the Electronics Module, was completed in early February. Follow-up analysis of the test data and hardware inspection is on-going. Vibration testing was conducted to help ensure that the VIIRS science instrument will withstand the rigors of launch.

"This milestone is significant because it means that VIIRS is on the path to thermal vacuum test, the final test overall and in the environmental series," said Dave Vandervoet, vice president and NPOESS program manager for Northrop Grumman's Aerospace Systems sector. "With each step forward, we are gaining confidence that VIIRS will perform at the high levels expected of this next-generation sensor."

Preparations for thermal vacuum testing are underway and will lead to an expected start of the test in April. The thermal vacuum test is the last environmental risk mitigation test. The test checks operations in orbit, and verifies sensor performance against key requirements. It is used to determine flight-worthiness of the instrument and to detect workmanship deficiencies that may affect performance on-orbit by subjecting it to flight-like operating conditions. The first VIIRS sensor will fly aboard the NPOESS Preparatory Project (NPP) satellite to be launched in late 2010.

"Testing thus far on VIIRS indicates that our design for this important sensor is solid," said Bill Hart, vice president for Raytheon's Space Systems group. VIIRS will collect data on atmospheric conditions, Earth radiation, ocean color and surface temperature in nearly two dozen spectral bands, with high spatial resolution.

Northrop Grumman is the prime contractor for NPOESS, leading a nationwide industrial team in its design, development, and operations. NPOESS will be an essential part of advancing the nation's environmental monitoring system that includes a stable and consistent platform for weather and climate monitoring.

Meanwhile progress on NPOESS' ground system, spacecraft, other sensors, and preparation for operations continues. In 2008:

  * The Interface Data Processing Segment that links the NPOESS science
   data products to the users was successfully installed and
   demonstrated at the Air Force Weather Agency.
 * Three of the five science instruments were delivered to the NPOESS
   Preparatory Project, a spacecraft that will both reduce risk for
   NPOESS and provide data continuity between NASA's Earth Observation
   System satellites and the operational NPOESS system.
 * The mission operations review was completed for the NPOESS
   Preparatory Project satellite and ground systems.
 * The majority of design reviews for the space segment were completed
   and a final critical design audit is planned for later this month,
   with a system-wide critical design review set for this spring.

Northrop Grumman Corporation is a leading global security company whose 120,000 employees provide innovative systems, products, and solutions in aerospace, electronics, information systems, shipbuilding and technical services to government and commercial customers worldwide.

  CONTACT: Sally Koris
         Northrop Grumman Aerospace Systems
         (310) 812-4721