Kinetic impactors and other space weapons

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LegioCI
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Joined: Fri May 06, 2011 3:15 pm

Re: Kinetic impactors and other space weapons

Post by LegioCI »

Out of curiosity, what sort of distances are we looking at for a "safe" jump vs. one that have a significant chance of failure? (Assuming no other factors are taken into account but distance.)
"But notice how the Human thinks. 'Interesting... how can I use this as a weapon?'" - Arioch

entity2636
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Joined: Fri Jan 12, 2018 11:53 am

Re: Kinetic impactors and other space weapons

Post by entity2636 »

LegioCI wrote:Out of curiosity, what sort of distances are we looking at for a "safe" jump vs. one that have a significant chance of failure? (Assuming no other factors are taken into account but distance.)
According to the Insider, safe jumps are <10LY, usually less (6...10LY). The safest jumps are between two single stars that have no gas giants around them and have no other massive objects or stellar remnants nearby as every concentration of mass influences your hyperspace trajectory and can pull you "off course". Multiple star systems are more dangerous to jump into because of how the two stars' gravity interacts with one another. Rapidly rotating stellar remnant systems (neutron stars, pulsars, etc.) are dangerous to impossible to jump into because of the gravity waves they generate. Hypothetically, you could safely jump into a lone star system (free floating star that's ejected from the galaxy) that's more than 10LY away, IF there are no gravitational anomalies along your course.

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RedDwarfIV
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Re: Kinetic impactors and other space weapons

Post by RedDwarfIV »

Something the WH40K meme did not take into consideration is that if it is expensive for you to push a rock towards a planet, its going to be significantly more expensive for the target to deflect it. The closer the rock gets to the target, the more delta-V is required to change its course.
If every cloud had a silver lining, there would be a lot more plane crashes.

Absalom
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Re: Kinetic impactors and other space weapons

Post by Absalom »

SVlad wrote:Starship Troopers - either the scenarist was a moron, or humans throw that asteroid themselves in a false flag operation (conspiracy!).
The movie director hated the book, so he intentionally did a bad job with the movie.

So, false flag it is.

icekatze wrote:hi hi
Gorbash wrote:...And keep in mind, this is a "lot" of power.
Everything you just pointed out applies to bombarding a planet with mass drivers too. This is a basic consideration of thermodynamics, energy in, energy out. I realize that this is has gotten away from the topic of Outsider, but the Warhammer 40k people need to check their math if they want to make general predictions about realistic costs/benefits.

Much of the point of using an asteroid as a weapon is to apply a low level of energy for a long period of time in advance, and sometimes taking advantage of an already high potential energy.
Within the 40k setting, it makes some sense.

In essence, anything defenseless enough to be hit with an asteroid is defenseless enough to be unable to oppose an armed landing. Anything dangerous enough to prevent an armed landing is dangerous enough to stop an asteroid if you give them time. So, either you don't need the asteroid, or you want the asteroid faster than it will arrive.

Also, remember that their paperwork is atrocious (armies destroyed decades before the paperwork gets finished), and that they might not be working in a location that they've sufficiently scouted before (or even scouted at all).


Really, the asteroid scenario makes the most sense for terrorists, planetary neighbors, and "trapdoor spider" aliens. As a general interstellar-warfare case, asteroids will always be more like lightning: outwardly impressive, but if your doing it intentionally you]re better off applying the same concepts in a different way (e.g. mine a comet for hydrogen, and use to fuel a fleet of KKV fusion-drives).

Using an asteroid instead of a missile is like using a tree branch instead of a mace: the missile will work better.

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