Next-Generation Weather Satellites

In January 1998, The Boeing Company of El Segundo, Calif., was awarded a contract from NASA's Goddard Space Flight Center in Greenbelt, Md. The contract currently includes the design, manufacture, integration and launch of three Geostationary Operational Environmental Satellites, GOES N, GOES O and GOES P. The GOES program is funded and operated by the National Oceanic and Atmospheric Administration (NOAA). Upon completion of N through P, the company will have built a total of eight spacecraft in the GOES series.

Based on the highly successful Boeing 601 spacecraft, the new satellites will provide more accurate location of severe storms and other weather phenomena, resulting in more precise warnings to the public. The three-axis modified Boeing 601 body-stabilized spacecraft design enables the primary sensors to "stare" at Earth and thus frequently image clouds, monitor Earth's surface temperature, and sound Earth's atmosphere for its vertical temperature and water vapor distribution. Atmospheric phenomena can be tracked, ensuring real-time coverage of short-lived dynamic events, such as severe local storms and tropical hurricanes and cyclones, two types of meteorological events that directly affect public safety, property, and ultimately, economic health and development.

Boeing will furnish the communications subsystem with a search-and-rescue capability to detect distress signals from ships and airplanes, and will also furnish space environmental monitoring instruments and operator training. Ground station upgrades will be provided by Boeing's teammate Integral Systems Inc. Boeing will also integrate three government-furnished instruments: an Imager and Sounder built by ITT Industries, Inc., and a Solar X-Ray Imager built by Lockheed Martin.

The imager is a multispectral five-channel instrument that produces visible and infrared images of Earth's surface, oceans, cloud cover and severe storm developments. The multispectral sounder provides vertical temperature and moisture profiles of the atmosphere, augmenting data from the imager. Sounder data are also used in computer models that produce mid- and long-range weather forecasts. A new Solar X-Ray imager will monitor the sun's X-rays for the early detection of solar flares. This early warning is important because these solar flares affect not only the safety of humans in high-altitude missions, such as the Space Shuttle, but also military and commercial satellite communications. The GOES satellites also carry space environment monitoring instruments, built by Assurance Technology Corp., which monitor X-rays, extreme ultraviolet and particle emissions including solar protons, alpha particles, and electrons. These space environment monitoring instruments also include a magnetometer, built by Science Applications International Corporation (SAIC), which samples the Earth's magnetosphere.

Stowed (left); In Orbit (right)

A data collection system on GOES receives and relays environmental data sensed by widely dispersed surface platforms such as river and rain gauges, seismometers, tide gauges, buoys, ships, and automatic weather stations. Platforms transmit sensor data to the satellite at regular or self-timed intervals, upon interrogation by the satellite, or in an emergency alarm mode whenever a sensor receives information exceeding a preset level.

The first Boeing-built GOES satellite, GOES D, was launched in 1980. This was followed by GOES E in 1981, GOES F in 1983, GOES G in 1986 (booster failed during launch), and GOES H in 1987. The GOES satellites transmit data collected to NOAA's Wallops, Va. ground station, which relays the data to the NOAA Satellite Operations Control Center in Suitland, Md. The information is then processed and distributed to users throughout the world.

The Boeing Company is the world's leading manufacturer of commercial communications satellites, and is also a major provider of space systems, satellites, and payloads for national defense, science and environmental applications.