Once upon a time, before there were satellites, spying was done with airplanes. Probably the most famous aircraft used for these purposes was the American U-2, which, despite the fact that it was designed in the early fifties of the last century, still flies in a slightly modified form. The U-2 was initially conceived as a surveillance aircraft for Soviet airfields and silos with nuclear missiles, it was used to fly over the USSR and Cuba, but later it flew over many other crisis areas in the world, mostly over the Middle East. The U-2 had revolutionary improved optics and was capable of resolving details of 30–60 centimeters on the ground, which was significantly better than the best cameras of the era, which, from the same height, had a resolution of seven meters.
photo: wikipedia.org…AND ON THE GROUND: U-2…
U 2 WAS
It was a slow glider-like aircraft with huge, slender wings that could stay in the air for ten hours at a time with the help of a single jet engine. The plane was difficult to control, difficult to take off and even more difficult to land, so that each flight required enormous physical effort from the pilot who could lose several kilograms of weight during the mission. By the way, the pilot was in a cabin with reduced air pressure, so he had to wear a spacesuit and an oxygen mask all the time.
The U-2 was not armed, it had only one huge camera with a lens diameter of 30 centimeters. It was "defended" only by its ability to fly at an altitude of over twenty kilometers, which American experts considered unattainable for Soviet radars and guided missiles. Every U-2 flight over Soviet territory was fiercely condemned by Khrushchev, but the Americans, despite this, continued with spying missions: after the launch of the Soviet "Sputnik" in 1957, the Cold War gained intensity and the need for information from the field was greater than ever.
photo: wikipedia.org...and Gary Powers in Soviet captivity
As time passed, American President Eisenhower became more and more reserved about this spy program. He doubted that the Soviets, with a bit of luck and further improvement of their defense systems, would ever catch up to an American aircraft. This is what happened in May 1960, when a Soviet SAM type missile exploded near a U-2 that took off from Pakistan with the intention of flying over the USSR along the south-north direction and landing in Norway. The plane was not seriously damaged but could not continue the flight, so the pilot had to force land on Soviet territory. The USSR thus got hold of almost the entire plane, which it would later use to build its own version of the spy plane (Beriev S-13). Pilot Gary Powers was captured and subjected to intensive interrogation, eventually being sentenced to three years in prison. He did not complete his sentence: he was exchanged for the Russian spy Rudolf Abel on the famous "Bridge of Spies" in Berlin in 1962. Overflights over the USSR were discontinued, but the U-2 was a great success for America: the plane photographed 15 percent of the Soviet territory during a multi-year campaign, and over 5000 spy reports were made based on those photos. On this occasion, Khrushchev asked Eisenhower for a public apology, but he never received it.
SATELLITE ERA
When satellites began to be used on a large scale, spy planes began to lose their importance. At first, satellites used classic film tape to store images. The illuminated film returned to earth in a capsule with a parachute that was caught in flight, a special "bucket" thrown out of the plane. The process was slow and prone to errors: very often it happened that several months passed from the moment of photography to the moment when the film was captured, developed and analyzed. During the "Samos" project, an attempt was made to develop a film on the satellite itself. The film thus developed was then scanned, and the scanned image sent to earth by radio link. The satellites did not last more than a couple of weeks - their useful life depended on the amount of film the satellite could carry. The stay in orbit was also limited by the low orbit around the Earth because, due to friction with the upper layers of the atmosphere, the height of the satellite decreased rapidly.
At the end of the seventies and the beginning of the eighties of the last century, digital CCD sensors began to be used instead of the classic film strip, similar to the ones you will find in every mobile phone or digital camera today. Satellites began to last longer, although limitations still existed: the space for storing digital photos is always limited, as are the number of opportunities to transfer the stored photos to earth (the satellite must be above a suitable receiver). Photos are huge, recording just one "scene" can take up several gigabytes (for the sake of illustration, a good camera that you can buy in a store uses only a few megabytes per photo).
photo: picryl / national reconnaissance officeTHIS IS HOW IT WAS ONCE UPON A TIME: Image of the Polish city of Poznań from the KH4A (Corona) spy satellite in 1965
There are four types of spy satellites today. The most significant are the optical ones, which record interesting objects on the ground with high-resolution cameras. The first American satellites of this type were launched as part of the Corona and Keyhole programs and were able to see details as small as two meters. They typically moved at altitudes of 120 to 300 kilometers. At those altitudes, the satellite constantly changes its position above the ground and is unable to continuously track one particular object. The largest satellite of them, KH-9, had a mass of 15 tons and because of its size it was nicknamed "Big Bird". Over time, the technology was perfected, so that satellites appeared that, thanks to their specific orientation in relation to the sun, can detect the movement of objects on earth based on the change in the size and position of their shadow. As technology progressed, so did the price: the KH-12 spy satellite cost over a billion dollars, a budget comparable to that of the Hubble space telescope.
In the second group there are satellites equipped with large radar antennas that have a lower power of resolution (up to one meter), but that is why they can "see" even through thick clouds that represent an insurmountable obstacle for observation in the visible part of the spectrum. The technology was perfected during the eighties ("Lacrosse" project), and the average price of satellites from this category exceeds 500 million dollars per piece. The third group consists of satellites that can eavesdrop on microwave (mobile) telecommunications in any country in the world. Finally, there are satellites that create an "information highway" around the country so that data from other spy satellites can reach the "headquarters" as quickly as possible (and often in real time).
SPY AND OTHER NEEDS
photo: ulalaunch / twitterNEW ERA: Launch of secret spy satellite
Although it is difficult to obtain accurate data, it is believed that at least one fifth of over 5.000 active satellites have the task of, in one way or another, observing the Earth's surface and the events on it. Some of these satellites are used for scientific or telecommunication purposes, but an increasing number of those used by the world's leading armies are used exclusively for espionage purposes. Today's spy satellites have colossal dimensions, and all the details related to them are a secret, including the "schedule", a clock that determines the time of the satellite's flight over a certain part of the Earth. Instead of a low orbit of limited duration, satellites increasingly operate from extreme heights: for example, the American NROL satellite from the "Orion" program has a mass of five tons and is able to observe targets on earth from a geostationary (equatorial) orbit, from a height of over 30.000 kilometers, all thanks to a huge parabolic antenna the size of a football field. At any given moment, the satellite can listen to more than a hundred telephone conversations at the same time. So far, more than 50 such satellites have been launched, and the total number of active spy satellites used by the US military is at least three times larger.
Other countries do not want to lose a step either. It is believed that Russia has at least 70 such satellites, while the number of Chinese ones is unknown. There are also France, Germany, Great Britain, Italy, India, Turkey, Mexico, Colombia, Spain, Denmark and Japan. None of these countries have more than ten operational spy satellites.
photo: wikipedia.orgCROWD IN ORBIT: Kompsat-3A, one of the many satellites watching us
What can all these satellites, say optical ones with CCD sensors, see? In their pictures are nuclear facilities, military units, agricultural fields, large ecosystems, suspicious ships, urban areas, architectural complexes, construction sites, areas threatened by storms and floods, smugglers, migrants, and often us, ordinary people... The minimum size of details that can be recognized in the images is a military secret, but it is believed that, in the case of today's average spy satellite, it is 10-15 centimeters (for comparison, the minimum size of details on Google maps is about half a meter). It's not enough to accurately identify a person's face or recognize a house number, but good enough to spot a man on a bicycle or a pet in the yard. There are indications that the leading military powers are working hard to develop a new generation of spy satellites with a resolution of only one centimeter. Private companies also have their own satellites for imaging from orbit, but their quality is legally limited: in America, for example, it is forbidden to launch civilian satellites capable of resolving details smaller than 30 centimeters. The principle is simple: no one can see everything that the army sees.
Let's return now to our minister Gašić, who requested from Germany (which, according to him, "protects the murderer Oliver Ivanovic", with or without a question mark, the devil would know him), asked for satellite images from the scene in order to confirm all that which the Serbian police already "knows". If these "satellite images" were really requested (the Germans say they were not, but what do they know), it would be said that the minister really does not understand how these images are made and what can be concluded from them.
In the movie "Mission Impossible 3", Ethan Hunt (Tom Cruise) meets an agent who has access to a satellite that can track people on the ground using the retina of the eye. Exactly what we need from the Germans to catch the killer of Oliver Ivanovic. The only problem is that this kind of technology only exists in James Bond-type Hollywood movies, while in reality, such a thing is decades away. Additionally, Germany does not have nearly enough satellites to cover every point on the globe so the chance that on January 16, 2018 its satellite was right over Kosovska Mitrovica is negligibly small.
Finally, fog is a serious problem for taking satellite images, even in London where it is foggy, as the minister says, "350 days a year" (which was not the case even in Sherlock Holmes' time, let alone today). Even if the conditions were ideal, even if the German satellite had been at the scene of the tragedy at the right time, the recording would not have allowed to positively identify the perpetrator. One would say that some current state of affairs is explained by evidence that we do not have. And we don't have them because they don't exist, nor have they ever existed.
