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Spies That Fly

Imaging With Radar
by Rick Groleau

 

Spies That Fly homepage

An unmanned jet plane flies high over the Afghan landscape, using a technology called synthetic aperture radar, or SAR, to search for signs of Al Qaeda. With its ability to "see" in complete darkness and through rain and clouds in the sky and snow and foliage on the ground, SAR (pronounced "sar" rather than "S-A-R") is becoming a regular component of unmanned aerial vehicles, or UAVs.

Other useful applications for SAR include mapping planets (such as the perpetually cloud-covered Venus), mapping terrain here on Earth, and even looking for signs of earthquakes. For some, what's most fascinating about SAR is not what it can "image" or even that it can produce remarkably high-quality pictures, but that an image can be created at all using radar waves and a moving antenna.


Analyze an Image

Analyze an Image (466k)
Requires Flash 5


Flash is a plug-in that allows for increased interactivity. If you can see the animated boxes at left, the plugin is already installed. If you do not see the boxes, you can install the Flash plugin.




Rick Groleau is managing editor of NOVA online.


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