By the early hours of the following morning, on Feb 25, military radar detected an unidentified flying object 120 miles offshore approaching the coastline.
Airborne technologies, such as different types of radar and photographic equipment carried by airplanes or spacecraft, allow archaeologists to learn about what lies beneath the ground without digging.
In fact, we kind of assumed that they were filtering a lot out, the way a sophisticated radar system can ignore echoes from stationary objects on the ground.
Many people think that ATC consists of a row of controllers sitting in front of their radar screens at the nation's airports, telling arriving and departing traffic what to do.
In the 1940s, ATC centres could and did take advantage of the newly developed radar and improved radio communication brought about by the Second World War, but the system remained rudimentary.
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30. 弗雷达为我热了一块馅饼,可我不能吃。
Freda heated up a pie for me but I couldn't eat it.