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Comment by cm2187 | Hacker News Reader

I actually wonder why these missiles were not left in orbit. Surely a missile launch directly from space would require much smaller missiles and even less lead time.

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I mean, the US had programs for that too. See the X-20 Dyna-Soar.

The genius of using the shuttle as a bomber is stealth. Not regular steath, but hiding in plain sight.

The USSR were worried the airforce could launch a shuttle with a nuclear bomb into an orbit near Moscow (or other targets), but claim it was just a regular launch with a regular payload with totally legitimate reasons for that orbit. Actually, with the shuttle's cross range ablities the orbit could be several hundred kilometers off the target.

And it would look like a regular flight as it climed into orbit and spend 20-30min floating towards Russia. Soviet command wouldn't be able to identify it as a threat until 3.5min before impact.

Ironically, now that the shuttle is gone, the X-37B is closer to this vision. It hangs up there for over a year at a time doing who knows what. And it has a ridiculous amount of delta-v to change its orbit.

There are plenty of things out there with lots of delta-v floating around doing who knows what. The X-37B is just the big public one.

AIUI, orbital mechanics makes leaving weapons in orbit not very useful. One missile on the ground can launch a strike at any location within its range at any instant the operator chooses, and deliver it within ~30m or so. One weapon in orbit can only strike locations along its current orbit, and at very constrained times. To deorbit something, you generally need a retrograde burn while it's on the opposite side of the planet as the place you want it to deorbit at. So even if you happen to be in exactly the right place to strike a particular target at the time you make the decision to, you still have to wait half an orbit, or ~45min for LEO. The time just gets longer for the location not being perfect or for higher orbits.

Article IV of the Outer Space Treaty prohibits nuclear weapons or other weapons of mass destruction in space. It's pretty hard to hide the fact that a satellite is full of nuclear material given that they stick around, but the shuttle would just be up for a little bit so it would be easier to hide things in it.

The Soviets did like to put anthrax warheads on their ICBMs targeted at cities and I suppose those won't have any distinctive emissions signature. But then again keeping anthrax spores alive in space with the thermal cycling and radiation can't be easy.

EDIT: But then again anthrax is a strictly counter-value rather can counter-force weapons. You would hypothetically put warheads in space for a quick counter-force strike so that plan wouldn't make sense.

Missiles left in orbit are only effective as first-strike weapons, because you just wait until they are over the enemy then launch your strike. As response or retaliation weapons they are useless. If the enemy launches an attack while your missile is in orbit over the Indian Ocean, or it's current cycle wont put it over the enemy for another 10 orbits, then you might as well not have it. This is why space based nukes were completely banned very early on.

You can setup an orbit to always cross over any single point on earth. Molniya orbit‘s are often used by communication satellite’s over Russia, but the US would not care about dwell time so would pick the opposite aiming to be close to the atmosphere over the old USSR.

Likely going for something closer to: https://en.m.wikipedia.org/wiki/GLONASS

Of course, I didn't say all such weapons would have to wait multiple orbits. The point still stand though that if you had a string of weapons in such an orbit, only a very small minority of them would be over the target area and ready to strike at any given time and they have terrible cross-range characteristics. Also Molniya orbits have quite long orbital periods, exacerbating the problem. The vast majority would have much longer strike times than surface based missiles. It only really makes sense to use orbital missiles if you deploy them as a swarm for a first strike.

You can synchronize each device’s orbit so every weapon is over every target at the same time. Worst case you need to wait for a full orbit to hit anything, best case you can hit everything within ~2-3 minutes.

Molniya orbits‘s are just an example. GLONASS uses a related orbit, but never comes that close to the atmosphere.

PS: You could do the same thing over the US including Hawaii and Alaska. You end up with different tradeoffs to keep things synchronized, but it’s not that hard of a problem.

If you launch a first strike, I don’t see why it would matter whether retaliation comes in half an hour or a day.

What would matter is whether that first strike or a later follow-up could take out the shuttle(s) before it could retaliate.

Did the USSR have capability to take out a space shuttle in orbit? I wouldn’t know. It wasn’t that high up (a V-2 could almost reach it), but accuracy of ICBMs wasn’t even good on stationary targets, and, I guess, you would need more of it in space, where ‘only’ radiation and heat would cause damage.

In case of retaliation you want it to be delivered soon, ideally before you and the retaliation infrastructure is destroyed. If the retaliatory strike is already in flight before the first strike can even reach the enemy territory (or sattellites, etc.) then it is much more difficult to prevent.

That's why the response time is so crucial. To ensure retaliatory strike strikes fear in your enemy (pun intended) you need to convince the enemy you are capable and willing to put your ICBMs before their ICBMs can even reach you. If you have only 2 minutes you need to convince the enemy you are willing and capable to do it within 2 minutes of detecting the strike.

You also want retaliatory strike to be delivered all at the same time as the best strategy seems to be in numbers. It is relatively easy to stop a single ICBM. It is completely different problem to stop hundreds of them each possibly containing multiple warheads. In this case the strategy is to deluge the enemy with warheads or, more precisely, hope they will not try to destroy you because they can never be sure to stop all out retaliatory strike.

The primary job of a first strike is to take out as much of the target's retaliation capability as possible. Objects in stable orbits are much easier to track, target and destroy that just-launched missiles (or shuttles) because you can take your time to identify them and line up your anti-satellite systems.

I cannot say for sure but here are four things that cones to mind:

- Considering how much of a problem normal space debris is I'm happy we don't have a number of old nukes in orbit.

- I also guess nuclear weapons need some maintenance.

- Leaving nuclear weapons in orbit would make it possible for another country to try to intercept/study/disarm them.

- Regulations/treaties about weapons in space

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