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Re:Powering the Lunar Base by taneq on Saturday August 07, 2021 @02:48PM (#28100884)
Also let's be honest, aircraft carriers are super awesome and fun and good for scaring brown farmers but in a modern war against an equal power they're not especially practical. Couple o' kinetic strikes and your $13 billion new toy is slag on the ocean floor for like, what... cost to get mass to LEO is $2600 per kg so if we want 100 special order deliveries of 1-ton rods from God that's $2.6mil per rod = $260 million to sink a $13 billion aircraft carrier and destroy how many billions of dollars worth of F22s and ammunition?

Like, I love aircraft carriers, they're so cool. But also physics says not so effective. :S

Re:Powering the Lunar Base by mLuby on Saturday August 07, 2021 @11:18PM (#28103950)
Rods from God are only simple at a high level, but as always the devil is in the details.

1. You have to position the rod satellite in the right orbit, or have enough so one is generally over the target.

2. Then when the order comes in to kill the carrier, your 1-ton rod plus satellite has to de-orbit from ~8km/s. Basically it needs the rocket that launched it, but up in orbit to drop it back down. (It's not quite so bad because gravity is assisting rather than fighting as during launch, but it's still a decent de-orbit vehicle.) The de-orbit takes time, and either you're dropping from ~1000km up or re-entering at some kind of ballistic arc from ~200km up.

3. Obviously the carrier will be maneuvering the moment that massive de-orbit burn is detected. So when course corrections will be necessary throughout the re-entry and maybe even into terminal flight, when your rod is hypersonic in the thickest part of the atmosphere, sheathed in sensor-blinding, comms-blackouting plasma.

(I'm assuming a CIWS—point defense gatling—throwing up a cloud of metal wouldn't do much to the rod, nor would an IR missile be able to hit the rod, but maybe those things could alter its trajectory enough to cause a miss.)

4. Then if you actually hit the target, did you over-penetrate it, smashing a 1m hole clean through the hull into the water, or did the rod explode like a bomb against the hull? (I assume the former but am very unsure here.) If it's just an unstoppable but small hole, damage repair teams would patch it and seal off those compartments to keep the ship fighting.

So in the end, you have a very expensive (let's use your $260M), unmaintainable hypersonic slug that everyone can see launch (and who launched it) and it might be able to poke some holes in a carrier.

Or you use normal hypersonic missiles, which should be harder to detect launching, more maneuverable, and might deliver explosive or nuclear payloads.

Or you launch a swarm of hundreds of relatively cheap anti-ship missiles and just overwhelm the carrier defenses that way.

So I agree the dominance of the carrier will last only as long as the next great powers war (and also that guided missile submarines might well be the future) but it's from fear of God raining down tungsten wrath.

Re:Powering the Lunar Base by dnautics on Saturday August 07, 2021 @05:49PM (#28102165)
Honestly the most important use of a carrier (especially for china) is going to be in supporting naval vessels interdicting against pirates harassing or stealing from oil tankers shipping from the middle east; china depends on mideast oil to feed its people. The us does not as of 2019-ish, and may in the short to mid term cease protecting international sea lanes especially in the mideast since we are rapidly disengaging out interests in the area (e.g. pulling out of Afghanistan).
Re:Powering the Lunar Base by jeffdn on Saturday August 07, 2021 @03:23PM (#28101133)
That’s also assuming that the satellite that drops said rods can maneuver into the orbit required to drop the rod without:

1. getting knocked out at the commencement of hostilities by an anti-satellite weapon

2. the Defense Intelligence Agency/National Reconnaissance Office noticing and telling the carrier to change course

3. getting blown up by an anti-satellite missile fired by an aircraft, or a member of the carrier’s strike group

Rods from god are a much more potent weapon when used against static targets!

Re:Powering the Lunar Base by xvilka on Saturday August 07, 2021 @11:10PM (#28103922)
There are more realistic scenarios today: hypersonic missiles and railguns. Both can't be mitigated by any known naval defense system.
Re:Powering the Lunar Base by nradov on Sunday August 08, 2021 @12:12AM (#28104148)
Of course they can be mitigated. Knock out the targeting or launching platforms and you break the kill chain. Plus hypersonic cruise missiles and railguns are still mostly in the research phase, and it's looking like railguns might not really be workable at all.
Re:Powering the Lunar Base by taneq on Saturday August 07, 2021 @03:31PM (#28101188)
1. Sure once we're under way but that doesn't change how good they are from a first strike perspective.

2. As a species we can land a rocket on a barge, do you think we can't land a big crowbar on a slowly moving target?

3. Might make 2 more difficult but a 1-ton tungsten rod is pretty durable.

Certainly more potent against a static target but with modern tech and one skilled, ethically ambivalent engineer, these days you could probably hit a row boat.

Re:Powering the Lunar Base by Andrew_nenakhov on Saturday August 07, 2021 @05:57PM (#28102249)
Because the barge is carefully positioned to be in a place this exact rocket drops from the sky.

Satellites are not 'sitting in orbit', they are falling on earth extremely fast, and not reaching it only because they fall sideways. Since they go very fast, they have immense momentum. To attack a target you have to steer that momentum elsewhere, and that takes a lot of energy and precision,and you also have a very small attack area for every satellite. So to cover all earth reliably you'll need a constellation with numbers like Musk's Starlink - i.e. thousands of satellites.

Re:Powering the Lunar Base by tsimionescu on Sunday August 08, 2021 @01:05AM (#28104332)
Do you really not understand the differences in difficulty between a cooperative, planned ahead rocket landing, and an adversarial attack on an actively evading target whose position may not be precisely known even at the start of the attack?
Re:Powering the Lunar Base by kcb on Saturday August 07, 2021 @03:18PM (#28101094)
I'd imagine in the opening phase of a war most orbital military systems aren't going to last very long.
Re:Powering the Lunar Base by ethbr0 on Saturday August 07, 2021 @09:41PM (#28103527)
Except for the highly manueverable and stealth (no emission) ones.

However, a huge amount of mass (for dropping) invalidates the former of those.

Re:Powering the Lunar Base by nradov on Sunday August 08, 2021 @12:17AM (#28104169)
Due to limits imposed by basic physics there's no way to build a really stealthy satellite. The power source, whether solar or nuclear, necessarily generates a large radar and/or IR signature that can't possibly be hidden from military grade ground sensors.

http://www.projectrho.com/public_html/rocket/spacewardetect....

Re:Powering the Lunar Base by ethbr0 on Sunday August 08, 2021 @04:58PM (#28110048)
Why do you need to be powered, if you're above atmospheric drag?

Just sit up there with a receiver, bank of charged batteries, and just enough awake to monitor for wake transmissions.

Re:Powering the Lunar Base by xvilka on Saturday August 07, 2021 @11:12PM (#28103933)
Thus it will be the end of space exploration for decades (or centuries) due to the Kessler syndrome.
Re:Powering the Lunar Base by manigandham on Sunday August 08, 2021 @04:26PM (#28109802)
What equal power? Even if you have the launch and weapons capability, kinetic bombardment from space is not effective against a moving vessel. Aircraft carriers are faster than you think. They're also incredibly important in air superiority, and controlling the air is what wins wars.

Assuming you can successfully attack one, you still have plenty of cruisers, assault ships, support craft, secondary/light carriers, subs, and several other carrier groups now headed straight for you. It's not like countries can't make a crazy plan to take out a single carrier right now, it's what would happen after that is the deterrent.

Re:Powering the Lunar Base by ethbr0 on Saturday August 07, 2021 @09:39PM (#28103508)
F-22s aren't carrier capable.

You're confusing the Air Force and the Navy.

Re:Powering the Lunar Base by dragonwriter on Saturday August 07, 2021 @11:18PM (#28103949)
> Cost to get mass to LEO is $2600 per kg so if we want 100 special order deliveries of 1-ton rods from God that's $2.6mil per rod

Who is that demonstrated a system capable of delivering these with a CEP that would give it, say, even odds of a hit on a carrier with 100 shots?

> aircraft carrier and destroy how many billions of dollars worth of F22s and ammunition?

$0 billion worth in of F-22s, because Sea Raptor never happened.

Re:Powering the Lunar Base by mr_toad on Saturday August 07, 2021 @10:53PM (#28103868)
Your typical impactor is going to take 10-15 minutes to hit the ground (or sea), so it’s going to be next to impossible to hit a moving target.