By using a longer wave length section of the infrared spectrum 

 (Nimbus HRIR infrared sensors operate in the range of 3.k to 4.2 

 micron "window") reflected sunlight will not contaminate the data 

 during the daytime portion of the satellite orbit. Stations having 

 APT facsimile receivers will be able, with minor equipment modification, 

 to receive infrared data on the same receivers. However, the infrared 

 data thus received may be of as low a resolution as the APT television 

 pictures . 



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