Lockheed Martin said Nov. 23 preparations have been completed for the engineering thermal vacuum testing of the payload for the first Space-Based Infrared System (SBRIS) geosynchronous satellite. Thermal vacuum testing verifies the payload functionality and performance in a vacuum environment. During the testing, the payload is stressed at temperature extremes greater than those expected during on-orbit operations.

The SBIRS payload, developed by Northrop Grumman Corp.‘s Electronic Systems sector, consists of a scanning sensor and a staring sensor, guided by the spacecraft’s pointing control assembly. The scanning sensor is designed for continuous observation and surveillance of traditional intercontinental ballistic missile threats, while the staring sensor is designed to detect very low signature, short-burn duration theatre missiles. The staring sensor recently completed flight acceptance testing.

When fully operational, SBIRS will consist of two payloads in highly elliptical orbit, four satellites in geosynchronous orbit, as well as fixed and mobile ground-based assets to receive and process the data. The first geosynchronous satellite is expected to be launched in fiscal year 2008.