|Mission type||Weather Satellite|
|Mission duration||17 years|
|Launch mass||352 kilograms (776 lb)|
|Start of mission|
|Launch date||December 7, 1966, 02:12:01UTC|
|Rocket||Atlas SLV-3 Agena-D|
|Launch site||Cape Canaveral LC-12|
|Semi-major axis||42,152.0 kilometres (26,192.0 mi)|
|Perigee altitude||35,782.0 kilometres (22,233.9 mi)|
|Apogee altitude||35,793.0 kilometres (22,240.7 mi)|
ATS-1 (Applications Technology Satellite) was the first experimental geostationary satellite, launched in 1966.[disputed (for: Syncom-3 was launched in 1964.) ] Though intended as a communications satellite rather than as a weather satellite, it carried the Spin Scan Cloud Camera developed by Verner E. Suomi and Robert Parent at the University of Wisconsin. After entering a orbit at 23,000 mi (37,000 km) above Earth, initially in orbit over Ecuador, it transmitted weather images from the Western Hemisphere, as well as other data, to ground stations, including well as video feeds for television broadcasting. It took one of the first pictures of the Earth's full-disk (the first from a geostationary orbit), on December 11 1966.
"For the first time," historians would note later, "rapid-imaging of nearly an entire hemisphere was possible. We could watch, fascinated, as storm systems developed and moved and were captured in a time series of images. Today such images are an indispensable part of weather analysis and forecasting." 
It was the first satellite to use frequency-division multiple access which accepted multiple independent signals and downlinked them in a single carrier. The spacecraft measured 56 inches (1,400 mm) in diameter, 57 inches (1,400 mm) high and weighed 750 lb (340 kg).
The ATS-1 would remain operational for more than 18 years, until April, 1985.
This satellite was cylindrical, with a diameter of 142 cm (56 in) and a height of 135 cm (53 in); an additional 270 cm (110 in) in height was the engine cover. The surface was covered with solar panels, and the whole satellite was stabilized by rotation.
A total of fifteen experiments were conducted during the mission: