EL SEGUNDO, Calif., May 9, 2006 /PRNewswire/ -- Raytheon Company's Visible Infrared Imaging Radiometer Suite (VIIRS) advanced sensor engineering development unit (EDU) has entered thermal vacuum testing, achieving another milestone for the National Polar-orbiting Operational Environmental Satellite System (NPOESS).

The testing occurs in one of Raytheon's space-qualified thermal vacuum chambers, which replicates the extreme heat and freezing cold cycles that spacecraft and sensors experience in space. This third and final stage of testing is expected to be completed by mid-summer.

Raytheon Space and Airborne Systems (SAS) business is under contract to design and develop the VIIRS EDU, the most advanced weather operational imaging sensor ever made, and to deliver three flight units with options for four more for NPOESS prime contractor Northrop Grumman Corp.

"This latest test phase advances VIIRS toward operational readiness on-orbit and continues to demonstrate that, working hand-in-glove with our customers, Raytheon is determined to ensure the nation benefits fully from the wide range of new capabilities promised by the most advanced weather technology ever," said SAS President Jon Jones.

VIIRS will collect visible/infrared imagery and radiometric data on the atmosphere, clouds, earth radiation budget, clear-air land/water surfaces, sea surface temperature, ocean color, and low-light visible imagery. The sensor will offer dramatic spatial, spectral and radiometric performance improvements compared with current operational capabilities.

"Recent successful tests, especially the vibration test, demonstrate the risk reduction effort on VIIRS is working effectively," said Alexis Livanos, president, Northrop Grumman Space Technology. "Northrop Grumman, Raytheon and our customer have worked very closely to move this program forward, and thermal vacuum testing represents another step towards retiring risk on NPOESS."

The EDU has successfully completed ambient testing and vibration testing, the first and second phases of system-level tests designed to ensure that the sensor will perform as intended and withstand the rigors of operation during launch and in space. The series of performance and environmental tests on the EDU, which is built using many of the same processes and design features used for the flight units, proves the processes used to design and manufacture the sensor are sound.

In another test, the EDU's passive cooling system, consisting of the cryo-radiator and other passive cooling elements, demonstrated better-than-required performance during thermal vacuum testing. This cooling system supports the sensor's infrared focal plane arrays, which are responsible for gathering imaging data.

NPOESS, the nation's next-generation, low-earth-orbit environmental satellite system, is composed of satellites, sensors, a ground-control system and a data processing and dissemination network. NPOESS will provide civilian, military and scientific communities with regional and global meteorological data; oceanographic, environmental, climatic, and space environmental remote sensing information; surface data collection and search and rescue capabilities.

Northrop Grumman Corporation is a global defense company headquartered in Los Angeles, Calif. Northrop Grumman provides technologically advanced, innovative products, services and solutions in systems integration, defense electronics, information technology, advanced aircraft, shipbuilding and space technology. With more than 125,000 employees, and operations in all 50 states and 25 countries, Northrop Grumman serves U.S. and international military, government and commercial customers.

Raytheon Company (NYSE: RTN), with 2005 sales of $21.9 billion, is an industry leader in defense and government electronics, space, information technology, technical services, and business and special mission aircraft. With headquarters in Waltham, Mass., Raytheon employs 80,000 people worldwide.

Note to Editors: Photos of the VIIRS sensor entering thermal vacuum test are available upon request.

  Raytheon Contact:
   Sabrina Steele
   310.647.9067

  Northrop Grumman Contact:
   Sally Koris
   310.812.4721

SOURCE: Raytheon Company

CONTACT: Sabrina Steele of Raytheon Company, +1-310-647-9067; or Sally
Koris of Northrop Grumman, +1-310-812-4721

Web site: http://www.raytheon.com/