Space Colony Warfare

[RedImperator]

It doesn't have to thrust for very long. All it has to do is get nudged a little and then inertia does the rest.

And then take forever to reach it's target.

Which is why I have already said that it's not a viable short term tactic.

And how do they get them there? It's anywhere between 2 and 3 and a half AUs to the main belt, and more than 5 AUs to the Trojans. That's months of travel with most realistic propulsion systems, and the belters can see them coming the whole way, unless Earth already has patrols in place in the belt, which would preclude this tactic, but would cost a fortune to maintain.

You're not thinking this through. If it's 2 to 3.5 AUs between the belt and months of travel with manned ships, then what's the point of making asteroids of doom? They'll take even longer to travel from the belt to earth; by which the war will be long over.

Which is why I have already said that it's not a viable short term tactic. The problem is not that I haven't thought this through, it's that you're not paying attention.

If the technology somehow exists to make these asteroids of doom reach Earth in 1 month, then the same technology also exists to allow much lighter ships to reach the belt or the asteroids faster from earth.

Where in my posts did I ever say asteroids could reach Earth in one month, save for Earth-crossers at or near their closest approach?

You're not thinking this through clearly. It takes far far less energy to move a thermonuclear device to the asteroid belt than it takes to move a really big asteroid large enough to screw life up on earth. And you've pointed the problem out here. If it takes months for Earth to retalitate and the Belters years or decades.....well....

Which is why I have already said that the tactic would be for sneak attacks and a deterrent against attack, not a short term strategy.

It costs money to do things like build warships of doom, etc. The only way the asteroid belt population and GDP could ever reach significant figures is if we invented unobtanium drive technology, because they would essentially be spacegoing banana republics, entirely dependent on the sale of whatever material their asteroid is made up; and because of the gargantugan amounts of stuff available from just a single asteroid, the prices of the raw materiels will be incredibly depressed.

And why exactly would their economies be dependent on exports to Earth?

1) They have to have their own industrial base, unless the drive technology is so wanked out shipping finished goods all the way from Earth is economically viable, which makes this whole debate irrevelant because they could get better results just slamming a ship at high speeds into the target.

2) They have all the mineral resources they need, including hydrocarbons and water for food production.

3) The delta-v requirements to move between asteroids is far less than between Earth and the asteroids. A single seed colony from Earth could spin off daughter colonies without any need for an unobtanium drive.

Link to Mike's Asteroid Calculator

Cratering energy is the energy required to blast out a crater of depth equal to the radius of the asteroid, which should easily result in its catastrophic disruption.

A 10 km wide asteroid would only need 180.9 megatons to crater it into smaller pieces which could be dealt with. Considering that the technology exists to create 100+ megaton fusion devices in the 1960s....

Did you read the part where he noted the calculator assumes the explosives are buried? Your energy requirements mushroom otherwise, because not only is at least half the device's energy wasted, but the energy produced is in the form of X-rays, which are not ideal for shattering a lump of rock.

[Nyrath]

But consider the implications.
Call me a cynic, but it seems to me that if the technology exists to alter asteroids into Earth collision trajectories, you can bet your bottom dollar that every single space-faring nations on Earth will have a branch of their astromilitary as an "orbit guard." They will be charged with patrolling the solar system to prevent unauthorized changes in asteroid orbits.

And it isn't just the L5 inhabitants and the asteroid rock rats that they will be keeping an eye on. An unfriendly nation could try to deorbit an asteroid on you that was small enough not to render all life extinct, but large enough to seriously damage your nation.

Any spacecraft carrying asteroid orbit altering equipment will be closely monitored, and probably escorted by a fleet of orbit guard ships of all space-faring nations. Those ships would suspiciously watch the spacecraft, and each other. On Earth orbit guard observatories would watch sthe skies for unexpected orbit changes.

From a delta-V standpoint, it is easier to alter the orbits of asteroids past the orbit of Jupiter. The drawback is that both the spacecraft travel time and the asteroid travel time would be several years.

[Nyrath]

I know it is impolite to reply to one's own posts, but this is interesting.
http://www.youtube.com/watch?v=3JHdYBet ... /index.php
It is a CGI movie of a Ceres-sized asteroid impacting the Earth

[SirNitram]

1) It's uphill all the way. First Earth orbit, then up the Sun's gravitational field. 'Roids will be going down the whole way.

Except if asteroid belt colonization is actually feasible, then we'll have drive technology to make such a problem academic.

Not at all. Everything costs. Even with fusion as a powersource, we'll worry about costs. And it will cost alot less to shove downhill than up.

2) 'Roids, if they can be thrown at Earth, can also adjust their orbits. A bit of thrust a few months before impact means you get the hell out of the way no problem.

Except the orbit has to intersect earth. That means that the asteroid can't whiz around the sky willy nilly. That means you're limited in how much "Evasive manuvers" you can do.

I wasn't very clear in writing. I meant to indicate that roids people live on can manuver.

3) As Red noted, a 'roid is rather difficult to kill with a nuke.

Link to Mike's Asteroid Calculator

Cratering energy is the energy required to blast out a crater of depth equal to the radius of the asteroid, which should easily result in its catastrophic disruption.

A 10 km wide asteroid would only need 180.9 megatons to crater it into smaller pieces which could be dealt with. Considering that the technology exists to create 100+ megaton fusion devices in the 1960s....

....Means precisely dick when the 'roid is coming straight at you and you can't bury the device. Toss a few dozen and life gets unpleasant.

[NRS Guardian]

Why can't you bury a nuke in an asteroid? Assuming you have the technology to mine asteroids, and that any asteroids headed toward Earth are going to take months or years to get here it should be possible to take a ship up to the asteroid and stick a nuke in it.

[GrandMasterTerwynn]

Why can't you bury a nuke in an asteroid? Assuming you have the technology to mine asteroids, and that any asteroids headed toward Earth are going to take months or years to get here it should be possible to take a ship up to the asteroid and stick a nuke in it.

Because, believe it or not, blowing up the asteroid is actually the most difficult of the options available to you. Giving it a bit of a nudge will send it into a new orbit which will miss Earth on that pass, and if you're good, every other pass into the foreseeable future. However, blowing apart an asteroid will fragment it. If you didn't take the time to carefully study the asteroid's geology beforehand, and place your nuke in the right place, it'll fragment in such a way that you'll possibly end up with a number of large pieces on an Earth-intercepting trajectory. And in that case, instead of a cosmic rifle bullet hitting the Earth, you'd now have a cosmic shotgun blast hitting the Earth. Imagine how fun that would be.