r/nuclearweapons

Summary The detonation of a nuclear weapon at an altitude of 400 km will damage or destroy a significant number of satellites, depending on the detonation's location. The effects arise from both prompt radiation and delayed effects trapped electrons (Argus effect).

Prompt effects through X-rays, gamma and neutros:

• A 15-kt detonation will place roughly 4 percent of LEO satellites at risk from prompt radiation.
• A detonation of 110 kt or greater will place all LEO satellites within the line of sight at risk (roughly 20 percent of all LEO satellites).

With 300 kt explosion ionizing damage threshold is 12,000 km, SGEMP damage threshold 4,000 km

Delayed effects (Argus effect: high-energy electrons trapped in L-shells):

Effects on satellites:

1. Lower-energy electrons can deposit on surfaces and exterior shielding, causing discharges that damage satellites.
2. Intermediate-energy electrons penetrate shielding (deep dielectric charging).
3. High-energy electrons can cause ionization and atomic displacements similar to high-energy X-rays and neutrons, destroying electronics (most electrons would be high-energy.)

>If a satellite has a design life of five years when exposed to 10^3 rads(Si), and a HANE exposes it to three orders of magnitude more, its life would be reduced by a factor of 1,000. This means its expected design life would fall to just a few days.

(note: linear degradation model where 1000-fold increase in radiation reduces lifetime 1000-fold is not realistic. Electronic component failure thresholds are non-linear. Many electronic components fail near instantly above specific radiation thresholds.)

I read about those here. Maybe they're deservedly classified and speculative, but are 'pulse shaping' devices not actually necessary for the miniaturized, smaller TN weapons actually deployed, and were maybe just used for large tests to prove a principle? Or they could be part of current TN technology efficiency?

The SA3000 was used (and still is) in the W88 475kt nuclear warhead used on the Submarine launched Trident II.  It runs the main computer/programmer responsible for altitude and fuzing calculations. 

Been going down a rabbit hole on the Damascus Titan II accident and I still can't wrap my head around how it started

September 1980, a maintenance crew is working in a missile silo in Arkansas. One airman drops a socket off his wrench. Just a socket. It falls about 80 feet, bounces off the thrust mount, and punches a hole in the missile's fuel tank

That's the whole trigger. Pressurized fuel vents into the silo for hours while everyone's scrambling to figure out what to do. Eventually it goes up, blows the silo's 740-ton closure door clean off, and throws the W53 warhead out into a ditch. Nine megatons, sitting in a field. It did not detonate. One airman was killed, around 21 injured

What gets me is how much of it came down to the warhead's safety design holding up under conditions nobody ever engineered for

Does anyone here know more about why the W53 stayed inert through all that? Always wondered how thin the margin actually was between 'didn't go off' and the alternative

Hi everyone,

I've been taking a bunch of measurements from photos to determine the W76's actual dimensions. I am now quite confident that the base diameter is 16" (406mm) and the length is 48" (1219 mm).

Next task for something I am putting together is the W88's dimensions. I could have sworn that I've seen an official image of the W76 and W88 side by side at some point, but have had no luck finding it. Is anyone aware of such an image? It would make it very easy to verify some rougher estimates I have of the W88.

Or would the solid and gas separate under the extreme acceleration before turning into plasma?

To comply with the New START treaty, bomber variants equipped to carry nuclear weapons were modified in such a way that their identification was possible from the satellites.

For B-52, it was the "New START fins"

https://preview.redd.it/zb5wo6nt7w8h1.png?width=659&format=png&auto=webp&s=df74088e703ea68b3922f7deb7ef0cbd04854c0d

(source: https://nautilus.org/wp-content/uploads/2024/08/Nuclear-capable-B-52H-Stratofortress-final-23-08-2024.pdf )

I'm interested in what kind of modifications were done to Soviet/Russian bombers for this purpose, but I haven't been able to find anything on the English internet.