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The Physics of Space Battles
An anonymous reader writes PBS' It's OK to be Smart made this interesting video showing us what is and isn't physically realistic or possible in the space battles we've watched on TV and the movies. From the article: "You're probably aware that most sci-fi space battles aren't realistic. The original Star Wars' Death Star scene was based on a World War II movie, for example. But have you wondered what it would really be like to duke it out in the void? PBS is more than happy to explain in its latest It's Okay To Be Smart video. As you'll see below, Newtonian physics would dictate battles that are more like Asteroids than the latest summer blockbuster. You'd need to thrust every time you wanted to change direction, and projectiles would trump lasers (which can't focus at long distances); you wouldn't hear any sound, either."
no one can hear you explode.
Go check out the GoG site for the two i-War games which feature "correct" space based combat.
Good old games, that were overlooked at the time.
Short bursts of thrust to get around? Wrong! Space is big... very big. Getting around a solar system would take days.
No fireballs in space? Wrong! Spaceship occupants need atmosphere.
Close in naval battles are a no-no? The is the distances lasers might be effective.
OK so we have long range battles... They say sci-fi lasers aren't possible but rockets are? It would probably be much easier to evade a rocket in space (a rocket that will probably fly past you at a crazy speed as it's course corrections have to fight inertia).
Actual space battles would be extremely boring to watch. It would all take place at such distances that nothing could really be observed very well or viewed as a whole. Assuming energy / laser type weapons, it's purely a matter of how sensitive and accurate the telescopes are that identify the enemy ships and direct the weapons where to fire. Stealth and cloaking would be where the real arms race would be.
Better known as 318230.
That sounds a little like submarine combat, as opposed to the surface naval or air combat that currently inspires our space battle sci-fi.
If you're going to have reaction drive style thrusters for maneuvering, you're going to run out of fuel very quickly, dissipating mass, unless your thrusters are thrusting out little bits of mass at VERY high speed, in which case they could be used as weapons themselves. (Sci Fi writer Larry Niven came up with the idea of a reaction drive as a weapon, google the 'Kzinti Lesson' for more info.)
I think it would be interesting to have space battles where several fighters were somehow connected to each other via some sort of tractor beam, so they maneuvered by transferring momentum between each other instead of dissipating mass into the vastness of space; they might look a bit like bolas circling each other but with quick changes snapping in and out as they went in to battle, or maybe they would be tethered to a mother ship, somewhat like World War II aircraft carrier that sends out figher planes to do the fighting. The mother ship would have enough mass to let the fighters seem to be free to zap around easily.
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("Cough Cough") I wrote an unpublished Sci Fi Novel (I did send it to a bunch of publishers at the time, over 10 years ago), where interstellar travel used 'draggers'. There was no faster than light travel so it took years and years to go between even nearby stars, (The travelers themselves would be in an accelerated frame of reference so it wouldn't be so long for them.) In the novel it took a long time to set up a system between two solar systems, similar to the way it takes a long time to set up a railway between two cities, but then you could use it very efficiently. A vessel would attach itself to a dragger, and be quickly accelerated (that's the hard part, dealing with the sudden accleration that would flatten everything against the back wall like you were in a super cream separator), the dragger, much more massive than the vessel, would be slowed down some, but then, at the other end, as the dragger wheeled around a star, the vessel would transfer it's momentum back to the dragger and slow down to become part of the other solar system.
The thing about conservation of momentum is that it means the center of mass of a closed system doesn't change. If two solar systems and the draggers going between them were a closed system, then the center of mass would shift as the vessel moved between one and the other, but, if the vessel returned to the original system again, then the original center of mass would be restored, and the energy used to move between them could be recycled, plus there wouldn't be reaction mass being spewed out all over the place.
In theory, theory and practice are the same; in practice they're different. (Yogi Berra & A. Einstein)
What gets me is when the author is painstaking in attention to detail in describing realistic ship movements in a 0 G vacuum, including relativistic effects, but then describes maneuverability as somehow being tied to a ship's "speed". It's another carryover from ships that maneuver via control surfaces that interact with the environment, and thus feels natural. But in a 0 G vacuum it doesn't matter at all whether it is ship A that just finished accelerating and ship B is "sitting still" or vice versa. Both situations are completely equivalent unless there is something else nearby, like a planet, that adds gravity or an obstacle to the situation.