remote sensing 
noun [mass noun]
The scanning of the earth by satellite or high-flying aircraft in order to obtain information about it.We compared the development of the marshlands in the last 25 years, and that is possible today because we have the information coming from remote sensing, from satellite, and you see that the marshlands decreased drastically....
- Circling just a few hundred kilometres above the earth, remote sensing satellites can monitor all that is happening in the skies and on the ground below them.
- It has made many subsequent forays into orbit, developing satellites for Earth observation, remote sensing, telecommunications and weather forecasting.