A Cold War Satellite Program Called Parcae Revolutionized Signals Intelligence
6 comments
·January 21, 2025perihelions
A few more comments of interest from yesterday,
https://news.ycombinator.com/item?id=42793564 ("A Spy Satellite You've Never Heard of Helped Win the Cold War (ieee.org)", 18 comments)
actionfromafar
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.
lupusreal
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.
jgrahamc
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
echoangle
> 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.
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...