The GOES (Geostationary Operational Environment Satellite) program provides vital data for the National Weather Service, providing terrestrial and space weather information to support military and civilian radio wave and satellite communications systems, electric power networks, the missions of Space Station astronauts and high-altitude aviators, and scientific research. The Aerospace Corporation has supported GOES throughout its mission lifecycle and is a key contributor to the upcoming GOES-R series.
Launched in 1975, GOES has evolved through new technological advancements and innovations, becoming essential to U.S. meteorological monitoring and forecasting. The GOES program is jointly operated by NOAA and NASA. NOAA provides the services and science derived from the data gathered by the satellites, while NASA procures, designs, builds and operates the spacecraft.
Today, NOAA maintains a two-satellite operational GOES system with continual coverage of the Western Hemisphere — one at GOES-East (slot at 75o W longitude) and the other at GOES-West (slot at 135o W longitude). The GOES spacecraft are equipped with an Imager and Sounder instrument package that is capable of capturing atmospheric phenomena such as clouds, precipitation, atmospheric motions, surface temperature, ocean color, and solar activity and is capable of detecting the evolution of severe storms.
In addition, GOES-11 through GOES-15 were equipped with the Space Environment Monitoring (SEM) instrument package that monitors solar wind particles and their variations. The SEM instrument package is provided by NOAA/SEC in Boulder, Colorado.
GOES satellites are controlled from NOAA’s Satellite Operations Control Center in Suitland, MD. During significant weather events, the normal GOES observation schedule can be altered to allow increased coverage of a specific region by request from the NWS.
The primary observations from a GOES satellite consist of radiances in a broadband visible and several infrared channels, saved as reflectance [percent] or brightness temperature [Celsius]. Observations are acquired in geostationary orbit, 35,790 kilometres (22,240 miles) above Earth’s surface. The GOES Imaging Spectrograph (ISG) and Atmospheric Sounder (ASS) instruments collect and record information about the atmosphere at different wavelengths, including infrared, visible and microwave. The sensors are able to scan the surface of the Earth continuously, allowing for real-time tracking of the development of severe weather phenomena.
The GOES satellites are equipped with the DCS (Data Collection System) that transmits environmental data to the GOES Space Environment Monitoring system. The DCS onboard the GOES satellites receives transmissions from remote automatic Data Collection Platforms (DCPs), and relays those data to small, ground-based regional data utilization centers via narrowband WEFAX transmissions. The DCS also processes and retransmits a variety of Level 1, Level 2 and higher data products. The geographic information for these data files is stored as tower location coordinates in the ABI fixed grid (horizontal and vertical x and y) and a corresponding tower geodetic latitude/longitude coordinate map to convert from tower geodetic coordinates to ABI scan angle coordinates. For example, to obtain ABI Level 1b and Level 2 products, tower locations are converted from their geodetic latitude/longitude coordinates into ABI horizontal and vertical x and y scan angles.