Detail Not Always Needed
William E. Stoney, a satellite specialist at a nonprofit company in McLean, Virginia called Mitretek Systems whose clients include the Air Force and NASA, said fine detail is not always what the military needs.
Military satellites can image objects with a resolution of "well less than a meter and probably down to centimeters," Stoney said. But these satellites focus narrowly and aren't useful for observing wide areas of terrain.
During the Gulf War, Stoney noted, the resolution of satellite images was limited to about 10 meters (33 feet) in black and white and 20 meters (66 feet) in color, but today's images capture at least 10 times more detail.
Among the most effective systems for one-meter (three-foot) imagery now in orbit are the French "Spot" commercial satellites and an American system called Ikonos, built by Lockheed Martin Space Systems in Sunnyvale and operated by Denver-based Space Imaging, Inc.
Some recent Ikonos images are now being made available free on the Space Imaging Web site, www.spaceimaging.com.
A new commercial satellite called Quickbird, owned by the DigitalGlobe Corp. in Longmont, Colorado, is scheduled to be launched later this week from Vandenberg Air Force Base in California. Quickbird is said to provide images with the highest resolution of any civilian satellite—down to about two feet (60 centimeters) in black and white or eight feet (2.5 meters) in color and infrared wavelengths.
Image Analysis Has Improved
Along with sharper-eyed satellites, military planners also have much more powerful analytical tools to make sense of the data sent back to Earth.
Specialized optical filters, for example, can bring out many previously invisible details—shadows and ruts from tanks, for example. By combining different satellite images of the same scene, analysts can reveal all sorts of unsuspected detail, Franklin said, although the precise techniques involved are classified.
And it is not only satellites that provide crucial images, Franklin said.
Drones, the small unmanned aircraft that fly low by remote control, are taking close-up images over Afghan territory.
Cameras in the nose cones of cruise missiles, the "smart weapons" of modern warfare, transmit images of their targets right up to the moment they hit. They can also send back close-ups of the target's immediate surroundings—other buildings, for example, or structures such as oil tanks and airport towers that might become fresh targets.
Copyright 2001 The San Francisco Chronicle
