HOW DOES IT WORK?

 

There are three primary types of spy satellite. The first is the good old space camera. The first generation of these were launched into orbits about 150 miles above the surface. They carried high-resolution film cameras and were stationary above their targets. During the night, they would lie dormant, but during the day they snapped thousands of pictures. Photography was automated—the technology at the time meant that no active targeting was possible. These things spent thousands of feet of film on locations the CIA only hoped had interesting activity in it.

The resolution of the cameras got down to around seven feet—enough to identify vehicle types, count people, and differentiate landscape features from buildings, but not enough to ID individual people or read a street sign. By and large, these photos were intended to supplement the effort of intelligence workers on the ground—confirming human intelligence and providing direction for future operations and the targeting of weapons.

When the 30,000 feet or so of film contained in the satellite was exhausted, it ejected a canister filled with the negatives, which plunged through the atmosphere. A few miles from the ground, the canister would deploy a parachute, which allowed specialized planes to recover it in midair. The satellite itself eventually crashed into the atmosphere and burned. A few days later, the CIA would go to Walgreens, pick up the developed pictures, and see all the things they missed in Russia over the last few weeks. In terms of actionable intelligence, it was a pretty lame way to gather information, but it could offer some insight into the long-term actions of an enemy.

The government jealously guards the secrets of modern satellite technology, but some educated guesses can be made about their capabilities. The cameras they carry now are digital. Private satellites have been launched with camera resolutions as tight as two feet—more than enough to reliably identify individuals. Military technology typically exceeds civilian technology by a few years. So, the CIA could possibly be reading an enemy’s e-mail over his shoulder from space. Space cameras are even now busily counting the gray hairs in the Ayatollah Khamenei’s beard or totting up Kim Jong-il’s blackheads.

Likewise, advances in night vision and the resolution of infrared cameras indicate that darkness and thin cloud cover are no longer serious obstacles to the operation of a photographic spy satellite. As long as a target area has a small amount of visible light present—from stars, a campfire, or even candles—a military satellite can probably amplify it well enough to take high-resolution photographs.

Thick smoke or heavy cloud cover would block traditional cameras, but a technology called Synthetic Aperture Radar—used in spy planes and reconnaissance satellites sent to Venus—can penetrate even the thickest weather. SAR can resolve stationary surface features down to about four inches, enough to capture nearly as much detail as a photograph taken in full sunlight. It can’t resolve print, and movement in a target area could confound its ability to resolve detail, but it’s tight enough to see the Jumpman in a footprint in sand.

Back at the beginning of the space age, the real intelligence powerhouses were the second kind of satellite. Communications interception satellites are vast radar dishes that sit in orbits outside of those typically used by the microwave relay satellites that bounce radio signals around the world. Communications satellites are designed to only capture a tiny fraction of the microwave transmissions fired at them from the ground; the rest speed off into deep space to one day interfere with alien prime-time TV. Interception satellites hang out higher up and capture those overflow transmissions. The bigger the radar dish the more it can capture—interception satellites are 100 feet or more across.

Many of them were originally operated by the NSA as part of the program that would eventually become ECHELON. Others were run by the CIA or the air force. During the Cold War, when the vast majority of civilian and military communications traffic was routed through satellites, this type was vastly important, but their numbers have diminished with growing reliance on Earth-based communications networks.

The third type of spy satellite didn’t make its appearance until later in the space race. Measurement and Signature Intelligence (MASINT) satellites are a broad class of craft packed with specialized sensors intended to scan for certain types of activity, analyze materials, detect chemicals, and perform other remote analytic tasks. MASINT satellites typically work in conjunction with image intelligence satellites. A space-based camera might take a picture of a new type of enemy missile; a MASINT satellite could determine what material the missile’s hull is constructed of, analyze its engine flare to deduce propellant type, track its acceleration and velocity, and map its trajectory to assess payload and range. Space cameras only see part of the picture; MASINT satellites complete it.

Other, less common types of spy satellite include those pointed specifically at known enemy nuclear-missile sites, tasked with detecting a launch; and compact communications satellites equipped with extremely powerful microwave transmitters designed to relay secure tight-beam transmissions to covert operatives with minimal risk of interception.