So, how sensitive are those nuclear early warning satellites the US, etc., use here on Earth? I believe they can pick up our larger tactical nuclear weapons, but how about the smaller (tenth-kiloton) ones and down from there? Anyone know?
I’m a mite curious as to whether having a firefight with FSTM bullets (laser-triggered fusion thermal; yields from a ton to a tenth-kiloton) would show up, leading to a sudden panic at NORAD from all the NUCFLASHes pouring in.
If I’m not mistaken nuke-flash satellites sense the whole light-curve and use the length of delay between the double-flash phenomenon to judge yield. For something as small as 0.1-1 kt the satellite might just reject it as a false-positive even if it picked it up.
Davy Crocketts (or rather, W54s) could apparently go down as low as 10t, so I’d assume some provision has been made to detect nukes that small. Whether it’s the same satellites that detect larger nukes, I have no idea.