We saw in many movies that people were being tracked by spy satellites. Though it is widely believed that such technology would really be available as we saw many high resolution pictures of the Earth taken by satellites, we are not too worried about us being seen as satellites are expensive. Unless you are a high value target, as the government put it technically, no one would bother to move the satellite camera towards you. The Earth surface is large and satellites are few. It is extremely resource intensive to target the satellite at someone on Earth.
But a cheap version of high altitude surveillance of similar effect may get some people worried. As introduced in the video below, development of this cheap version is complete. We could be watched in details from above, 24 hours a day. The idea is to put a wide angle camera in the sky which could take continuous video and store it for future use. The project is call Argus, and it provides a “Wide area persistence stare”. One camera can take wide angle video of an area of 15 sq mile with a resolution of 1.8 gigapixel.
A simple question comes into mind. How come they can made such a large camera? Is the technology mature and is it very expensive? The answer is a big surprise. The engineer has a simple solution. He took the cheap camera sensors of 368 smartphones and combined them in an array to produce high resolution video, which could zoom in to an object of 6 in wide on the ground. The camera could produce continuous snapshots of an area of 15 sq mile, which is about half of Hong Kong Island. The video files are stored; so what happened a few days ago on the ground could be analyzed subsequently in details.
To put the camera in the sky, UAV Unmanned Aerial Vehicle is used. This flying robot could take the camera to an altitude of 17500 ft, and stay at the same location for a very long time. The engineer refused to confirm whether the US government has given the green light for the surveillance to proceed. But we all know what “decline to confirm” means. A small UAV 10 ft across 17500 ft above would be impossible to be seen. But if a few of them are always there above a city, anything exposed to the sky could be recorded no matter what. On the good side, we could be very safe as crime detection, crime investigation, accident prevention, search and rescue operations are all benefited from such additional information. On the privacy side, we are being watched every time we step out of the house.