SECTION 1 

 INTRODUCTION 



1.1 GOES System Description 



1.1.1 What Is GOES? 



The United States of America Geostationary Operational Environmental 

 Satellite (GOES) service is an integrated system of Earth and space 

 environmental sensors which provide nearly continuous observational 

 information to ground-based user stations. The service is operated 

 and controlled by the National Oceanic and Atmospheric Administration 

 (NOAA) of the U.S. Department of Commerce, and was developed at the 

 National Environmental Satellite Service (NESS) in conjunction with 

 the Synchronous Meteorological Satellite (SMS) program of the U.S. 

 National Aeronautics and Space Administration (NASA). 



1.1.2 How Is the GOES System Implemented? 



The GOES service currently operates two satellites located in Earth- 

 synchronous orbits approximately 35,500 kilometers above the Equator 

 at longitude 75°W and longitude 135°W. Both satellites are controlled 

 from the NOAA Command and Data Acquisition (CDA) Station at Wallops 

 Station, Virginia. 



1.1.3 What Does GOES Do? 



The GOES service performs five missions. Each of the missions 

 is carried out by a dedicated subsystem, as described below. 



1.1.3.1 Visible and Infrared Spin-Scan Radiometer (VISSR) 



Each satellite has a visible/infrared radiometer that provides nearly 

 continuous imaging of the viewed portion of the Earth's surface and 

 cloud cover. The visible images are produced during daytime, whereas 

 the infrared images provide day and night coverage. 



1.1.3.2 Retransmission of VISSR and WEFAX Data 



The CDA is uniquely equipped to receive the high-speed VISSR data from 

 the spacecraft. These data are reformatted at the CDA and retransmitted 

 through the spacecraft transponder to Satellite Field Service Stations 

 (SFSS) within view of the spacecraft. SFSS activities located in 

 San Francisco, California; Kansas City, Missouri; Suitland, Maryland; 

 Miami, Florida; Honolulu, Hawaii; and Anchorage, Alaska, currently 

 receive and process, the retransmitted VISSR data for distribution to 

 weather forecast stations throughout the United States. 



In a similar fashion, Weather Facsimile (WEFAX) pictures are transmitted 

 through the spacecraft transponder to such users as ships at sea, 

 aircraft, and weather forecast stations located within view of the space- 

 craft . 



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