The Applications Technology Satellite (ATS) 



The ATS series includes research and development satellites built 

 for NASA's Goddard Space Flight Center. Launched into both equatorial 

 and geo-synchronous orbits, these satellites have returned spectacular 

 full-disc television pictures of the earth both in color and in black 

 and white. 



Two ATS satellites, ATS 1 and ATS 3, attained their designed orbit 

 while a third, ATS 2, went into a highly elliptical orbit which eventually 

 caused satellite tumbling and picture failure. ATS k, a very sophisticated 

 satellite, lasted 2 months in orbit, but due to stabilization difficulties 

 was unable to send any data to receiving stations. A fifth satellite j 

 scheduled to be launched in August 1969) will not have a camera system 

 as part of its scheduled experiments . 



The basic ATS spacecraft is a cylinder 5^-0 inches long and 57-6 

 inches in diameter with solar cell arrays mounted around the periphery 



for power. ATS 1 weighed 775 pounds. 



The geo-synchronous orbits into which ATS 1 and 3 were launched are 

 prograde orbits (i.e. in the direction of the earth rotation) of 2k hour 

 period. Thus, having matched the rotational period of the earth, these 

 satellites appear to hover motionless over fixed locations. 



The Spin Scan Cloud Camera (SSCC) of ATS 1 and the Multicolor Spin 

 Scan Cloud Camera (MSSCC) and Image Dissector Camera System (IDCS) of 

 ATS 3 take pictures every 20, 2^ and 2^ minutes respectively. Thus, they 

 are able to discern diurnal cloud changes (and indirectly indicate possible 

 oceanic changes in the surface structure of the ocean). These television 

 pictures are transmitted to ground data acquisition stations at Rosman, 



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