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A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

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Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#2
Some time in the late 1990s I was lying on the grass in my back garden in the Bay Area. It was a clear night and I was just watching the sky when three satellites flew over in formation. I don't know which satellites I saw but they were almost certainly part of a related program: https://www.satobs.org/noss.html

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#3
This sentence stuck out to me: "MAD, which so far had dissuaded either side from launching a nuclear strike, could tilt in the wrong direction"

The thing about M.A.D. is that there is no right direction on the tilt. An imbalance in either direction encourages all parties to strike first.

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#5

This sentence stuck out to me: "MAD, which so far had dissuaded either side from launching a nuclear strike, could tilt in the wrong direction" The thing about M.A.D. is that there is no right direction on the tilt. An imbalance in either direction encourages all parties to strike first.

Except not actually, because even if nuclear power is imbalanced, nuclear war is still too dangerous for anybody who's not as crazy as General Ripper.

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#6
Blackman[1] is a 1986 textbook that includes an example of a naval tracking application with observations every 90 minutes. It was obvious to me that the observations were satellite based and TIL they must have come from this system.

It's an excellent book. Used it heavily during my PhD.

[1] https://uk.artechhouse.com/Multiple-Target-Tracking-with-Rad...

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#7
post #2

Some time in the late 1990s I was lying on the grass in my back garden in the Bay Area. It was a clear night and I was just watching the sky when three satellites flew over in formation. I don't know which satellites I saw but they were almost certainly part of a related program: https://www.satobs.org/noss.html

> NOSS satellites locate and track ships at sea by detecting their radio transmissions and analyzing them using the TDOA (time-difference-of-arrival) technique.

Very cool, basically inverted GPS.

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#8
post #2

Some time in the late 1990s I was lying on the grass in my back garden in the Bay Area. It was a clear night and I was just watching the sky when three satellites flew over in formation. I don't know which satellites I saw but they were almost certainly part of a related program: https://www.satobs.org/noss.html

Many years ago I saw the ISS overhead with a second smaller dot near it. This was the space shuttle (can't remember which mission) that had recently undocked and was still in the vicinity. Very pleasing!

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#9

This sentence stuck out to me: "MAD, which so far had dissuaded either side from launching a nuclear strike, could tilt in the wrong direction" The thing about M.A.D. is that there is no right direction on the tilt. An imbalance in either direction encourages all parties to strike first.

Except not actually, because even if nuclear power is imbalanced, nuclear war is still too dangerous for anybody who's not as crazy as General Ripper.

MAD stands for Mutually Assured Destruction.

They type of imbalance that is being talked about removed the "Mutual". So total destruction of your opponent and minimal to no damage to your side.

This is why things like "decapitation strikes" where you destroy the leadership and prevent enemy launches were considered.

This is also why the U.S. has a nuclear trident: Land ICBM, Sub SLBM and Strategic bombers that are ready to take off the moment a launch is detected. To ensure that for any strike against the U.S. there would be retaliation.

What the imbalance or lack of mutual would lead to is either:

   A. Stronger force strikes first in order to win the conflict.
   B. Weaker force strikes first because they know that stronger force will strike to try and win.

Re: A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence

#10
post #2

Some time in the late 1990s I was lying on the grass in my back garden in the Bay Area. It was a clear night and I was just watching the sky when three satellites flew over in formation. I don't know which satellites I saw but they were almost certainly part of a related program: https://www.satobs.org/noss.html

> NOSS satellites locate and track ships at sea by detecting their radio transmissions and analyzing them using the TDOA (time-difference-of-arrival) technique. Very cool, basically inverted GPS.

Except they didn't. The sats were sensors that relayed data down. Systems on the ground did the calculations. I imagine there was another revolution when proper computers started being put in orbit to do the math locally, vastly reducing the needed bandwidth.
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