GOES is a family of geostationary weather satellites that measure Earth-emitted and reflected radiation from which atmospheric temperature, winds, moisture and cloud cover can be derived. The first GOES satellite was launched on October 16, 1975 and since then the agency has continued to improve its technology to ensure its accuracy and reliability.
During a normal day, the GOES satellites are positioned 35,790 km (22,240 mi) above the Earth’s surface. This allows them to continuously image clouds, monitor the Earth’s surface temperature and water vapor fields and sound the atmosphere for its vertical thermal and vapor structures. This provides a detailed picture of the evolution of the Earth’s atmospheric phenomena.
It is also able to provide information on solar-terrestrial interaction and the environment in and around Earth’s magnetosphere, providing real-time data to the Space Environment Services Center (SESC) for monitoring, forecasting and alerting to geomagnetic storms and other significant events. The SESC is a major part of the National Oceanic and Atmospheric Administration’s (NOAA) Earth science mission.
The GOES instruments on board a GOES-R satellite consist of an infrared imaging and sounding instrument called the Imager, a geostationary lightning mapper (GLM), a solar ultraviolet imager (SUVI) and a space environment in-situ suite (SEISS). These instruments are a part of NOAA’s Earth Observing System, which is operated by the National Oceanic and Atmospheric Service (NOAA).
In addition to the GOES satellites, there are several other geostationary orbiting weather satellites operated by countries world wide that contribute to coverage of the entire planet. These include the European Organisation for the Exploitation of Meteorological Satellites (EOGS), the Japanese Meteorological Agency (JAXA) and China’s National Satellite Observing System (NSOS).
A GOES-R satellite is a geosynchronous satellite that orbits at 35,790 km above the Earth. It is used for continuous observations of the United States, the Pacific and Atlantic Oceans, Central America and South America.
GOES-R is being built by Lockheed Martin using the A2100 satellite bus and will be launched in November 2016 on an Atlas V 541 expendable launch vehicle. The GOES-R series is the fourth generation of GOES satellites and will extend the operational life of the GOES satellite system through 2036.
It uses an array of infrared and visible instruments to measure the sun’s radiation in the wavelength ranges between 0.3 and 1.25 micrometers. The GOES-R satellites can measure a variety of meteorological parameters, such as cloud top height, air temperature and wind speed.
These instruments are sensitive to long and short wavelengths of the thermal infrared radiation that is emitted by the Earth’s surface, cloud tops and water vapor in the atmosphere. Some of this radiation is absorbed by oxygen, carbon dioxide, ozone and methane in the atmosphere, while other wavelengths are reflected back toward space by ice particles or other cloud structures.
The long wavelengths of the infrared radiation are absorbed by the atmosphere at higher elevations, so GOES-R satellites have a special band called the High Infrared Imaging Sensor (HIIR). It is primarily used for cloud top height and ice particle detection but can be useful to determine air temperature.