Orbital bombardment

[frigidmagi]

Missiles have a number of drawbacks.

1: You have to bring your own, as far as I know there are no naturally occuring nuclear missiles or what not floating about the solar system.

2: You have to pay for them. Rocks are free long as you can find them.

3: Missiles are easier to shot down then an rock the size of Rhode Island for example. To say nothing of the one the size of Texas.

[Shark Bait]

Missiles have a number of drawbacks.

1: You have to bring your own, as far as I know there are no naturally occuring nuclear missiles or what not floating about the solar system.

Does a radioactive asteroid count? I mean its more of a dirty bomb but hey radiation is radiation.

[Stofsk]

If it absolutely had to happen, there'd be a way. One possibilty is good old missles, just like we have today, except with powerful attittude thrusters and the same manner of heat sheilding that is used for space shuttle re-entry.

Except at has been pointed out in this thread before (which has BTW been dormant for two months before your post) you can basically achieve the same by throwing really big rocks at the planet.

Throwing rocks at a planet is slower, will almost certainly be detected (assuming the defenders are of the same tech level as you are; if they throw stones themselves but whilst wearing bearskins, then this discussion is moot), and if they can respond then there's always a chance that they can divert the rock's path. Using missiles however means you deploy your weapon with the initiative. Because your missiles are being carried by your warships, who can deliver their weapons more or less at their discretion and a lot quicker than the rockrats can. There's a reason why throwing rocks is considered the poor man's alternative, and it's really only possible if you have the high ground.

[Stofsk]

Missiles have a number of drawbacks.

1: You have to bring your own, as far as I know there are no naturally occuring nuclear missiles or what not floating about the solar system.

Yeah, you do. But so what? Assuming these are warships they're going to be outfitted with weapons to begin with, because that's their mission. In other words, this isn't a bug it's a feature. Any hard sf space warship is going to carry missiles that are more likely that not gonna be nuclear.

2: You have to pay for them. Rocks are free long as you can find them.

Rocks are free, but there ain't no such thing as a free lunch. Moving the rock requires some force to divert it's orbit into a new one that will hit the target. I'd like to know how to divert a rock without using a nuke; even if there were a way, space vessels cost money to operate, so effectively you're still paying some cost. It may actually be more cost, if it turns out that jumping into orbit of the planet and dropping your bombs is cheaper than finding a convenient asteroid and sending it on it's way to its target, in a timeframe that is acceptable, and making sure the target can't divert the rock the same way you diverted it in the first place.

3: Missiles are easier to shot down then an rock the size of Rhode Island for example. To say nothing of the one the size of Texas.

You wouldn't shoot down an asteroid. You'd divert it's orbit into a new one that is not aimed at your planet. If you can divert a rock from its regular orbit to strike a planet, then you can do the opposite - divert it from hitting your planet. 'Shattering' the rock would cause many problems, and would actually be a cure that's worse than the disease.

In comparison, a missile can be designed with ECM as well as evasive maneuvering, decoys, multi-vector entry systems, and other defensive systems that give it a better chance of surviving reentry and striking its target.

[Surlethe]

Does a radioactive asteroid count? I mean its more of a dirty bomb but hey radiation is radiation.

A large asteroid will generate its own radiation upon entering the atmosphere: because it's traveling so quickly, it essentially heats the air in front of it so much the gas is superheated and ionized. As it expands, it's basically a huge, cylindrical explosion, with all the effects of a nuclear blast. (ref: here)

When you're looking for bombardment, one thing you might want to think about is medium- and small-sized space rocks. It's not a bifurcation between planetary extinction event and nothing; the Tunguska blast, e.g., which was only ("only"!) about 1000 times the magnitude of Hiroshima -- certainly not a global extinction event -- and was caused by an estimated 50 m diameter meteor. Newtonian mechanics are such that you can accurate predict the entry of a vehicle (we do it all the time with the shuttles), and if you get a relatively small meteor, you can drop it with relative accuracy and impunity without the large-scale effects associated with asteroid blasts, and yet retain otherwise cheap and unprecedented destructive power.

To take an example, suppose you have a nation which exists in the asteroid belt -- call it P1 -- and one which exists on Earth (P2). If P1 can destroy P2's space capacity, P1 can simply launch small asteroids from the belt toward the Earth. It shouldn't be difficult for a society that is advanced enough to survive in space to plot a course which takes an asteroid from the belt and drops it on a city on Earth a year or three later. P1's got to be patient, but P2 is ultimately fucked.

Addendum: Do keep in mind that this strategy is predicated upon space dominance, which you presumably already possess if you're in a position to conduct orbital bombardment.

[Comrade Tortoise]

Throwing rocks at a planet is slower, will almost certainly be detected (assuming the defenders are of the same tech level as you are; if they throw stones themselves but whilst wearing bearskins, then this discussion is moot), and if they can respond then there's always a chance that they can divert the rock's path.

And even so, it will still work better because you can do it all damn day. If you use a mass driver to hurl the asteroids at your leisure.

We arent necessarily talking about diverting the natural orbit of an asteroid. We could just as easily talk about plucking local, smaller asteroids out of their orbits and using a mass driver to chuck them at a planet. If you do that, you will be able to do it all day with a suitable supply train, and it doesnt matter how great the planetary defenses are, you will eventually wear them down as you will be able to do this from beyond their effective targeting range. It is much easier to hit a city using a calculator to target your mass drivers while blind, than it is to do the same targeting a ship.

A missile needs to be transported a long distance. It needs fuel, and is hella expensive per shot. It also suffers from the glaring weakness that it can easily be detected with even passive sensors and shot down due to it providing its own propulsion. It ir runs out of fuel, just like an asterid it's path can still be diverted.

Using missiles however means you deploy your weapon with the initiative.

You can do that with a rock as well. Like an siege, the attackers control the engagement.

Because your missiles are being carried by your warships, who can deliver their weapons more or less at their discretion and a lot quicker than the rockrats can.

Moot if your warships are armed with mass drivers

There's a reason why throwing rocks is considered the poor man's alternative, and it's really only possible if you have the high ground.

Moot, see above. It is the poor man's alternative, but it is still efficient and deadly.

Yeah, you do. But so what? Assuming these are warships they're going to be outfitted with weapons to begin with, because that's their mission. In other words, this isn't a bug it's a feature. Any hard sf space warship is going to carry missiles that are more likely that not gonna be nuclear.

Indeed. But look at it from a logistics standpoint.

You have a limited supply of missiles. A functionally unlimited supply of big rocks. You have a lot of time typically. If you plan on taking a planet, or bombarding it into the stone age, it is safe to say you have orbital superiority and thus control of the engagement.

It makes more logistic sense to hurl rocks. They are free on their own, and need to be transported a shorter distance to be used.

Provided your ships are armed with mass drivers

Rocks are free, but there ain't no such thing as a free lunch. Moving the rock requires some force to divert it's orbit into a new one that will hit the target.

nuclear warheads are not cheap either. They require construction, fuel, and transport to combat theater.

I'd like to know how to divert a rock without using a nuke; even if there were a way, space vessels cost money to operate, so effectively you're still paying some cost.

Use a grapple (or gravitic tractor beam... whatever), and apply the force of your engines to change it's acceleration, then use a mass driver to chuck it. You can use the ships in your supply train for every step sans the chucking. You still pay some cost, but it is probably going to be less per kiloton of destructive power than making a missile, transporting that missile a comparatively long distance, then providing the energy in terms of fuel to propel said missile.

It may actually be more cost, if it turns out that jumping into orbit of the planet and dropping your bombs is cheaper than finding a convenient asteroid and sending it on it's way to its target, in a timeframe that is acceptable, and making sure the target can't divert the rock the same way you diverted it in the first place.

I am pretty sure they wont have time to send little cargo ships out to grab asteroids hurling at them. Especially when your own warships have control of orbit.

You wouldn't shoot down an asteroid. You'd divert it's orbit into a new one that is not aimed at your planet.

How?

If you can divert a rock from its regular orbit to strike a planet, then you can do the opposite - divert it from hitting your planet.

Not necessarily. If you are using gravitic tractor beams maybe, but not if you are using little tugboats to physically push/pull small to medium sized asteroids for use in a mass driver... they would have no way to stop that.

[Surlethe]

You don't even need ships equipped with mass drivers; you could simply nose up to an asteroid and then push it in the direction you want, or point your rocket's nozzle at it and nudge it with your exhaust in the direction you want. Really, the only thing stopping you from throwing rocks at someone is their ability to divert the rocks into a harmless orbit -- an ability they don't have if you've got space superiority.