Early spy satelites even used film; I remember reading about one design that took a film picture, developed, and then used a CCD to scan it and send it back to earth, which is a bit mind boggling to me.
I would guess a development of Corona, the earliest spy satellites. Those earliest spy satellites were essentially disposable cameras. When full they dropped the film to be caught in mid air by the air force.
(A fascinating wiki hole - you may be gone some time) :)
Maybe I'm misremembering the spy satellites using this (keeping the images secret is harder is you transmit them), but Lunar Orbiter 5 worked this way, so we had the technology in the 60's
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The lunar Orbiter used an adapted E-1 camera from SAMOS. The E-2 and (canceled) E-3 also used the semi-dry development process and photomultiplier readout method.
That might explain why their film-based spy sats[0] used to return the camera as well as the film, unlike their US counterparts[1][2] that just returned the film capsule.
Makes me wonder how good the spy satellite pictures of the era were.
Wasn’t the technology behind the Corona satellites based on this tech? I wonder if the declassified pictures they release are the lower quality versions?
The 60s spy sats also took photos on film that were ejected in re-entry capsules and captured in mid-air using an airplane. Really crazy stuff they came up with and I'm surprised it actually worked. Engineering chops they sure had and balls too because capturing a falling object from space is pretty dangerous.
Of course then there were the soviets launching entire nuclear reactors into orbit for a few months' worth of radar duty. Ok the US did one too but it was just one. All those Russian cores are still in orbit except the two that crashed.
Pretty much. However the biggest change is the capability per kilogram that can be packed into a satellite now. Today a 3U cubesat weighing roughly 20kg can take thousands of images, process them locally to manage for weather effects and orbital skew, and then transmit them to a single ground station several times a day.
The first spy satellites weighed tons and literally dropped film canisters back into space to re-enter and be recovered by aircraft or helicopters which would then take the film to a laboratory to be developed[1]. Typically, a satellite would take a few weeks to both stabilize in the environment in space, calibrate its optics, take some test photos for analysis, re-calibrate based on those results, and then be ready to go.
True. Shuttle was begun long before digital imaging and asymmetric encryption did away with film. Of course shuttle could also be used as a recon platform itself, one that could alter orbit radically as needed to conduct surprise overflights. The MOL/Almaz programs, manned spying stations, were still in the back of people's minds.
Sometime around the time the shuttle went live, the military discovered CCD or similar cameras and encryption.
The "Keyhole" satellites used to parachute down film canisters, which would be scooped up by a plane while descending on the chute - caught in-flight to avoid capture by other nations.
Most definitely there was a very good video about lead engineer (I think) talking in front of a hexagon spy satellite from the 1970s a lot of the information on it is declassified now, but he did say that the resolution on them still was and all he could say was that in the 1970s "I could read a newspaper on a table" and that's all he'd say on the matter.
imagine how far technology has come along since then
Back in the 70s spy satellites used film cameras and used to return the film in re-entry capsules. There’s a _really_ good (fictional) move called Ice Station Zebra about a retrieval mission in the arctic that goes wrong.
Retrieving the satellite allows you to safely recover the film, and re-equip the satellite with new film and propellant. The latter is important because it’s useful for spy satellites to be able to change their orbits frequently to observe new targets or evade tracking.
Also bear in mind some spy satellites are huge and incredibly costly. The Hubble Space Telescope is based on a spy satellite series.
My favorite part was the technology used to return the photos to earth:
Once a reel of film was finished, it was loaded into a re-entry pod and sent back to earth. "And then at around 50,000 feet, a parachute would slow it down, and a C-130 airplane caught it in midair over the Pacific," Pressel says.
There was a very large US program to send up a photo sat manned, take pictures, and send back to earth in very small pods. It is a good read I will update post if I can find video.
>> The idea would be that the astronauts would be able to take pictures and interpret film on-orbit
That is a modern take on the problem. At the time, the astronaut's role was to interpret the situation and ensure the best photographs were taken. Getting a spy sat to point at the correct location, at the correct time, and take a good photograph was a huge engineering challenge. But a person looking through a viewfinder could ensure that every snap was useable rather than another picture of Russian trees. They were never going to sit in space with magnifying glasses and do actual image analysis, a process that takes hours and many different people. They would evaluate a target for the most interesting details and ensure those details made it into frame.
And unlike satellites, a manned station could take photographs of targets of opportunity, targets that cannot be pre-programmed such as a moving ship.
They also made cameras. Ever hear of the wildly popular Brownie? Anyway their film expertise does not take away their involvement in cameras for spy satellites in the 1960s.
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