FWIW, there has been a number of nuclear explosion tests in our atmosphere: https://en.wikipedia.org/wiki/Tsar_Bomba
Further your ignoring submarines and early proximity detonation on the nukes. The most likely result of building such a system is an early nuclear EMP clearing orbit before the nukes get through anyway.
Really any of the nuclear material will just disperse into the atmosphere relatively harmlessly, especially if it's somewhere over an ocean. Plutonium in seawater measures in the parts per billion anyway.
Having several pounds of plutonium burn up in the atmosphere just means it will be spread over a very wide area which is much worse than a chunk of it falling somewhere.
When the enemy attacks, you have minutes to contact the president (in the us case) and he has only minutes to decide, which way it goes. You have to get your planes flying and launch your icbms before they get destroyed from the incoming missiles.
There is no time to wait and see, one of the first things that will happen is, that the enemy is detonating a nuke in the upper atmosphere near your land or near the horizon of your radars. The electromagnetic radiation blinds your radar and from now on you are blind. No radar how many missiles where launched after the initial firing.
Your have to counter strike with full force, now! Now or never, the probability is very very high that you will only have this chance, before many of the people in the chain of command are killed, nowhere to be found or incapable to act. Somewhere in the us, there will be someone in the chain of command that is authorized to act, but the person has not much to do. That will not happen in days, that will happen in hours, probably in the first 2.
The icbms will hit in the first 25-40 minutes, that planes will take hours, but think about it: the pilots and crew will deliver the bombs at any cost, because there is nothing to go home to.
Submarines will also fire a few missiles to strategic targets, but will mainly act as backup, IF you need them after the first „rodeo“.
There is also to this day no concept of ending a nuclear war. How to contact the enemy to make peace, when everything is gone. Who can you trust, who is the real person in charge.
In reality, the living will envy the dead.
There is nothing, except cost, preventing the US from building enough Aegis/Aegis Ashore/THAAD launchers to defend the entire US. The recent Iranian strike was a useful small-scale live test of the technology, but both Aegis and THAAD have been tested and worked on for long enough for the US to have reasonable confidence in them.
This is not including things like laser weapon descendants of YAL-1, or Starship deploying Brilliant Pebbles en masse into orbit, or thousands of Starshield satellites watching every inch of the planet (and/or carrying Brilliant Pebbles). They would be helpful, and possibly superior, but Aegis and THAAD are enough, in theory.
Helping Ukraine defend against the invaders is not "poking the bear".
For example he could set off a single low-yield high-altitude explosion to demonstrate that he "means business". And watch with delicious expectation as the Western world shits its pants.
It is unfortunately a comparatively low-risk, but sickeningly attractive proposition for him to consider -- especially if he finds himself backed into a corner with his own survival threatened (as will be the case if the war reaches a point where he is seen to be intractably failing).
Assuming he means, "shorten the time to deliver the nuke," I'm guessing he is mistaken here: having the nuke in orbit lengthens the time needed to deliver the nuke, not shorten it.
https://nap.nationalacademies.org/catalog/13189/making-sense...
(Sorry you have to login as guest to download the PDF)
This compares to ~20-30min for existing ICBMs and their ground based interceptors
In particular, when the goal is to intercept an ICBM, the enemy helpfully raises the target to be (briefly) at the same altitude as the satellite. (An ICBM's max altitude is much higher than low-earth orbit.) If the goal is for a satellite to attack a city, the enemy does not helpfully raise the city to orbital altitudes.
I also don't understand why intercepting faster is worth anything.
Orbits are very unintuitive things. For starters they're much higher than a suborbital trajectory.
You would also need to pre-target to stage in orbit and at that point you're locked into that trajectory unless you brought A LOT of extra fuel. This would inevitably be slower and less flexible regardless.
The only way for this to have any advantage is to stage a ton of nukes in orbit at different trajectories, which is politically insane.
Yeah I just don't see a technological solution to nuclear explosives. Several countries have enough nukes to kill the whole population of earth multiple times over.
Even without rockets at all I can imagine alternative ways a nation could get nuclear explosives into all the major cities of another country if it was life-or-death.
The question for this type of system isn't "Could I picture any scenario where it works?" but rather "Can I picture any scenario where it doesn't?"
https://skeptics.stackexchange.com/questions/460/do-we-have-...
I guess it depends on how you want to wipe out humanity. Nuclear winter or ecosystem disruption might do it, but explosions and radiation probably won't.
There is nothing, except cost, preventing the US from building enough Aegis/Aegis Ashore/THAAD launchers to defend the entire US. (See my full comment elsewhere.)
>Even without rockets at all I can imagine alternative ways a nation could get nuclear explosives into all the major cities of another country if it was life-or-death.
No such alternative delivery method is 100% guaranteed to get through to the target as ICBMs were (until recently). There is always the risk that a ship carrying nukes is intercepted, that a weapon smuggled into the enemy's territory is detected, that counterintelligence will identify agents before they can act, etc.
In a MAD scenario, nuclear weapons have to be 100% effective, barring the odd technical failure. Otherwise the enemy will respond in kind.
These would be ideal as interceptors staged in orbit onboard Starlink/Starshield satellites.
Just look at: https://www.alumnifounders.com/
Calling this "connected to Starshield" is pretty nonsense.
Massively decreasing the per mass cost of delivering any kind of cargo has huge and complex implications.
Massively decreasing the per mass cost of delivering cargo across oceans was a big deal.
Massively decreasing the per mass cost of delivering cargo across continents by rail/road was a big deal.
Massively decreasing the per mass cost of delivering cargo by air was a big deal.
"Big deal" here means all kinds of things, but let's talk about war.
Every one of the above mentioned steps caused radical changes in how wars were fought.
What have we seen over the past few years, even prior to 2022, in terms of drones? Massively decreasing the cost of precisely delivering small explosives over short ranges, with drones in this case, has been a game changer.
Even without a fully functional and reusable Starship system, SpaceX has greatly decreased the cost, cadence and reliability of delivering cargo into space. I understand the price they charge for individual launches is only 'somewhat' below the competition. That incremental but rather sudden decrease has already opened up a lot of doors.
A fully reusable Starship system drops that cost by at least another order of magnitude.
We are on the cusp of another revolution in warfare, and it's happening far, far more quickly than any of the other previous revolutions.
Imagine hundreds of thousands of smart kinetic munitions in many LEO orbital inclinations. According to https://en.wikipedia.org/wiki/Kinetic_bombardment a 20kg tungsten kinetic munition in LEO would deliver about 11 tons of TNT to the ground. Each SpaceX fully reusable launch to LEO could deliver about 2,000 of these. I didn't look it up, but I believe SpaceX has done about 150 Starlink launches so far. If each of these had delivered 2,000 kinetic munitions, there would already be 300,000 up there.
As far as I know, there's absolutely no defense against this kind of munition. In LEO they're moving at about 8km/s, and just before sea level impact they're moving around 3.5km/s. At best there could be a few minutes of warning.
Any entity that controls such a constellation would have what is effectively absolute and permanent air supremacy while risking no 'friendly' human life.
As far as command/control/tracking/sensing? Very low $/kg to LEO fixes that too. See Starlink and Star Shield, right now.
Nobody can predict how this will go, except that it will definitely 'go' in unexpected directions.
Mars is a great way to inspire engineers that would otherwise not work at defense companies.
I can't find him _ever_ touching the subject, which is strange given it's huge significance.
Just when I thought the modern disconenct from physical reality couldn't get any worse...
https://news.ycombinator.com/item?id=40509016#40518795
> I've very recently seen numerous posts starting to show up on both reddit and various websites as well as anonymous wikipedia editors pushing this conspiracy theory. They all repeat the same thing. They'll claim Griffin as basically a founder of SpaceX (who in reality had almost no involvement with starting SpaceX) and they'll claim Griffin basically "gave" SpaceX its first government contracts even though NASA administrators have almost no sway over where contracts go (that'd be illegal). They'll also claim other things like that Starlink is somehow developing weapons to be put in orbit to reproduce SDI.
