The New York Times reports on amateur "satellite spotters who, needing little more than a pair of binoculars, a stop watch and star charts, uncover some of the deepest of the government’s expensive secrets and share them on the Internet."

Thousands of people form the spotter community. Many look for historical relics of the early space age, working from publicly available orbital information. Others watch for phenomena like the distinctive flare of sunlight glinting off bright solar panels of some telephone satellites. Still others are drawn to the secretive world of spy satellites, with about a dozen hobbyists who do most of the observing....

John E. Pike, director of GlobalSecurity.org, a private group in Alexandria, Va., that tracks military and space activities, said the hobbyists exemplified fundamental principles of openness and of the power of technology to change the game.

“It has been an important demystification of these things,” Mr. Pike said, “because I think there is a tendency on the part of these agencies just to try to pretend that they don’t exist, and that nothing can be known about them."...

The Visual Satellite Observers Web site (http://www.satobs.org/satintro.html) describes the appeal of satellite spotting this way:

Amateur astronomers seeking new challenges, find that spotting faint, rapidly moving satellites, such as the tiny Vanguard 1 (America's second satellite), are comparable to spotting a distant galaxy. Tracking down a newly launched spy satellite in a secret orbit, tests analytical as well as observational skill. Observing the International Space Station transit the sun, moon or one of the planets, requires planning, perseverance, and often a bit of luck.

However, according to the Times, "The government’s relationship with the hobbyists is not a comfortable one. "

Spokesmen for the National Reconnaissance Office have stated that they would prefer the hobbyists not publish their information, and suggest that foreign countries try to hide their activities when they know an eye in the sky will be passing overhead.

The satellite spotters acknowledge that this may be so, though they doubt that such tactics are effective.... Mr. Pike said the officials who complained about the hobbyists “don’t like it, but they’ve got to lump it.” Despite the many clever ways that the spy agencies try to minimize the likelihood that their satellites will be spotted, he said, they will be. And that, he said, is a valuable warning: a world with so many eyes on the skies renders deep secrets shallow.