# "Real" Physics in Space Battle **URL:** \ **Category:** Cafe Society\ **Created:** [October 13, 2016, 2:21pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418 "2016-10-13T14:21:45Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![swampspruce](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/swampspruce/32/261_2.png) [@swampspruce](https://boards.straightdope.com/u/swampspruce)\ **Post date:** [October 13, 2016, 2:21pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/1 "2016-10-13T14:21:45Z")
This [thread](http://boards.straightdope.com/sdmb/showthread.php?t=537013&page=2http://) got me to thinking about all the sci-fi space operas I’ve read/watched and began to wonder if anyone has done a space battle that in any way respects orbital mechanics/ physics in space? I know it would be very counter-intuitive (no “pew=pews” of the turbo lasers, 3-d battle space, no fabulous engine noises, engines on only when changing vectors) but would it be cool/worth watching? ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [October 13, 2016, 2:54pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/2 "2016-10-13T14:54:01Z")
You definitely should check out “The Expanse”. There are 5 novels, and one season of a TV series produced by the Syfy channel. The show is excellent so far, while the books start good but IMO aren’t quite as interesting later on (though I’m only on book 3). It’s set in a near-future solar system where the Earth government is in conflict with Mars, itself in the early stages of terraforming, and the “Belters” which populate the frontier of the asteroid belt and the moons of the outer planets. Off of planets, “gravity” is only provided by rotation or constant thrust. Ships are given (admittedly unrealistic) powerful and efficient drives, which can sustain 0.3 G burns indefinitely and high-G burns in short bursts. There are a few spectacular space battles, going from long-range salvos of torpedoes and countermeasures, short-range dueling with kinetic projectiles, and eventual boarding operations in zero gravity. There’s also lot of fascinating world building examining how fragile life would be in a series of rickety Belt stations and mining ships, and how society and biology might adapt to the circumstances. Air and water, in particular, are precious resources. They’re the basis for a lot of conflict between colonies and the inner planets, or workers and their corporate overlords. But among the Belters, there’s zero tolerance for screwing with any precious supplies: a slumlord might be tolerated, but when they start skimping on air recycler maintenance, they’ll be tossed out an airlock at the earliest opportunity. If you want to keep going down the hard scifi rabbit hole, check out the website [Atomic Rockets](http://www.projectrho.com/public_html/rocket/). It’s a massive collection of essays and commentaries about “realistic” hard scifi (scroll down to the bottom to get the whole list of topics). To get started, you might also want to check out their [list of books movies, and games that get the science “right”](http://www.projectrho.com/public_html/rocket/sealofapproval.php). ---
**Author:** ![bob\_2](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bob_2/32/3341_2.png) [@bob\_2](https://boards.straightdope.com/u/bob_2)\ **Post date:** [October 13, 2016, 3:21pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/3 "2016-10-13T15:21:48Z")
I have always imagined that space battles would not be dissimilar to sea battles in sailing ship days. Ships would take hours to manoeuvre into a ‘good’ position, and missiles fire from too far away would be easily avoided or destroyed. Of course, if FTL speeds are posited then that doesn’t really work - or does it. In O’Brian’s books we see captains trying to predict the intentions of the opposition; “getting the wind gauge” was vital. They got up to all kinds of _rue de guerre_, false flags etc, but it all seemed to happen in slow motion, with only a brief burst of action at the end. ---
**Author:** ![cmyk](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/cmyk/32/3353_2.png) [@cmyk](https://boards.straightdope.com/u/cmyk)\ **Post date:** [October 13, 2016, 3:31pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/4 "2016-10-13T15:31:39Z")
It makes me wonder what sort of weponry and artillary would be developed, so you wouldn’t have to depend on direct hits. I’m thinking of anti-aircraft type shells, but with nuke charges that would spread shrapnel at crazy speeds, with a cone of safety that you would be sure to align with your own ship. Also set off a huge EMP. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [October 13, 2016, 3:35pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/5 "2016-10-13T15:35:54Z")
Babylon 5 did a pretty good (but not perfect) job of depicting realistic physics in its space battle scenes. –Mark ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [October 13, 2016, 3:56pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/6 "2016-10-13T15:56:32Z")
IMO the most unrealistic aspect of sci-fi spaceships is the propulsion / momentum. They seem to keep moving when the engines are running, and able to stop fairly quickly by stopping the engines. Even _Babylon 5_ spaceships appeared to behave this way. _The Expanse_ is the only exception I can think of. In this show & novels, the ships turn around and start decelerating halfway to the destination. An approaching enemy ship is visible long before the encounter, because they would be decelerating with their engines pointed towards you - otherwise they fly right past you with no time to do any damage. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [October 13, 2016, 4:14pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/7 "2016-10-13T16:14:19Z")
I thought that was one aspect that B5 got right. I don’t remember seeing ships stop when they turned off their engines. The little fighter ships in particular always seemed to be operating correctly in this respect. When they turned or slowed down, the various rockets on their wings would be firing in the correct way. The Vorlon and Shadow ships don’t count, though, because they’re using technology several billion years more advanced than ours, and may not be momentum-conserving. –Mark ---
**Author:** ![gnoitall](https://avatars.discourse-cdn.com/v4/letter/g/bb73d2/32.png) [@gnoitall](https://boards.straightdope.com/u/gnoitall)\ **Post date:** [October 13, 2016, 4:19pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/8 "2016-10-13T16:19:17Z")
> [@scr4](#): > > IMO the most unrealistic aspect of sci-fi spaceships is the propulsion / momentum. They seem to keep moving when the engines are running, and able to stop fairly quickly by stopping the engines. Even _Babylon 5_ spaceships appeared to behave this way. I don’t think you were paying attention to **Babylon 5** if you thought you saw that. Deceleration in open space was always by counterthrust. Cutting engines always meant coasting. Spacecraft didn’t bank and zoom. Hell, a typical combat maneuver in a Starfury fighter while being chased by a bad guy was to cut thrust, apply differential thrust across an axis to flip the fighter fore-and-aft while coasting, apply counterthrust to keep accelerating backwards, and target your pursuer with your forward-firing (from the spacecraft’s perspective) weapons. ---
**Author:** ![scr4](https://avatars.discourse-cdn.com/v4/letter/s/59ef9b/32.png) [@scr4](https://boards.straightdope.com/u/scr4)\ **Post date:** [October 13, 2016, 4:46pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/9 "2016-10-13T16:46:08Z")
It’s been many years since I watched _Babylon 5_, but I don’t recall the Starfury or any other ship turning around halfway to the destination. _Maybe_ they behave correctly if we assume they have forward-facing thrusters that are just as powerful as the rear-facing ones - which may make sense for a fighter but not for larger ships, I think. Earth Force destroyers clearly had big thrusters at the back, and nothing comparable in front, and we always saw them approaching the destination/target head first. ---
**Author:** ![lazybratsche](https://avatars.discourse-cdn.com/v4/letter/l/ba8739/32.png) [@lazybratsche](https://boards.straightdope.com/u/lazybratsche)\ **Post date:** [October 13, 2016, 5:29pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/10 "2016-10-13T17:29:06Z")
I’m with **scr4** : Babylon 5 had some references and nods to realistic physics, but most of the space combat wasn’t very far from “WW2 dogfighting and capital sailing ships in space”. I’ve got B5 ripped and sitting on a media server, so I’ll take a look at the big combat scene at the end of “Severed Dreams”: Star Furies (the fighters) are mostly zooming along in one direction, with thrusters at the back constantly glowing while making whooshing noises. There is a fair amount of gradual plane-like banking, though more extreme maneuvers are accompanied by extra glowy bits on the sides of the thruster pods (consistent with either lateral or reverse thrust). After an attack run, you see the Star Furies yaw 180° and going “backwards” relative to the “stationary” capital ships. I’ll call the physics “realistic” enough there. However, the destroyers and other large ships only have obvious thrusters at the back. Most of the time they’re slowly drifting towards each other, like ocean vessels. A few times the capital ships rotate in place, without any obvious thrust. Between scenes, they somehow end up stopped or traveling in different directions. If you want to be generous, you could say that there are either invisible reverse thrusters, or that all the pitch-and-burn deceleration happens off camera. Still, they’re doing their best boat impression, where they appear to trade shots while puttering around at 20 knots. There was one boarding pod that had obvious reverse thrusters that were used to decelerate right before latching onto a station. So, while there is some indication that everything obeys Newtonian physics, the set-piece battles are all set up to give images of fighters zooming around a fleet of slow capital ships. There’s very little consideration of how the _tactics_ would change if you had ships with high thrust and practically unlimited Δv. In any case, it was remarkably better than contemporary Star Trek for at least giving a few nods to real-world physics. ---
**Author:** ![Doughbag](https://avatars.discourse-cdn.com/v4/letter/d/aeb1de/32.png) [@Doughbag](https://boards.straightdope.com/u/Doughbag)\ **Post date:** [October 13, 2016, 5:45pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/11 "2016-10-13T17:45:50Z")
The space battles in Evan Currie’s Odyssey One series make great effort to seem plausible. Marko Kloos also tries to have believable space battles in his Frontline series. So does Richard Fox in his Void series. Of cos they all have that technology that let them travel faster than light, but I can live with that, but you have that in almost ever Sci-Fi galactic space battle book/film. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [October 13, 2016, 5:46pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/12 "2016-10-13T17:46:53Z")
> [@scr4](#): > > It’s been many years since I watched _Babylon 5_, but I don’t recall the Starfury or any other ship turning around halfway to the destination. _Maybe_ they behave correctly if we assume they have forward-facing thrusters that are just as powerful as the rear-facing ones - which may make sense for a fighter but not for larger ships, I think. Earth Force destroyers clearly had big thrusters at the back, and nothing comparable in front, and we always saw them approaching the destination/target head first. Yes, the Starfuries had four engines, each with two nozzles, one pointing forward and one pointing backwards. They would slow down by firing all four forward-pointing engines. They would turn by firing the forward engines on one side and the backward engines on the other side. [Here’s](https://www.youtube.com/watch?v=nanfQ0mviaU) a short clip showing one maneuvering. I’m sure there are better examples showing more complicated maneuvers but I can’t put my finger on one right now. I’m pretty sure the Starfuries always showed correct physics with regard to their engine operation. You may have a point about the bigger ships; I don’t really recall how they maneuvered. One point where the physics was probably wrong is with the ships that had rotating sections for artificial gravity. They seemed to maneuver without regard for gyroscopic effects. –Mark ---
**Author:** ![GreenWyvern](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/greenwyvern/32/2834_2.png) [@GreenWyvern](https://boards.straightdope.com/u/GreenWyvern)\ **Post date:** [October 13, 2016, 5:55pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/13 "2016-10-13T17:55:28Z")
The best space battles I’ve ever found in SF books are those in C.J. Cherryh’s ‘Alliance-Union’ novels. _Downbelow Station_ (which won the Hugo Award for best novel) is the first and most essential book for that universe. In the space battles, there are delays in info and communications, which travel only at light speed. So you can see where the enemy ship \*was \*a few seconds or minutes ago, but you don’t know what it’s done since then. But the ships may be moving at significant fractions of light speed - not easy to change course. Real physics, aside from the hyperspace jumps, and brilliant writing. Her novel _Hellburner_ is without doubt the best book about the _development_ of space warships. It’s a sequel to _Heavy Time_. Her work has something else very rare in SF - real, believable, complex characters. ---
**Author:** ![markn\_1](https://avatars.discourse-cdn.com/v4/letter/m/f9ae1b/32.png) [@markn\_1](https://boards.straightdope.com/u/markn_1)\ **Post date:** [October 13, 2016, 6:11pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/14 "2016-10-13T18:11:40Z")
> [@markn\_1](#): > > [Here’s](https://www.youtube.com/watch?v=nanfQ0mviaU) a short clip showing one maneuvering. Also notice the clever launching technique. Babylon 5 is a rotating space station, and the Starfuries are docked at the outer rim. To launch, they merely rotate outward (“downward” with respect to the artificial gravity) and release the clamps holding them in place. They are then flung outward by the centrifugal force of the station, without any need to use propellant. –Mark ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [October 13, 2016, 6:24pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/15 "2016-10-13T18:24:50Z")
Since the OP is asking about whether such battles have appeared in films, and whether they would be cool to watch, this is better suited to Cafe Society than GQ. Colibri General Questions Moderator ---
**Author:** ![Chimera](https://avatars.discourse-cdn.com/v4/letter/c/8e8cbc/32.png) [@Chimera](https://boards.straightdope.com/u/Chimera)\ **Post date:** [October 13, 2016, 6:35pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/16 "2016-10-13T18:35:40Z")
> [@lazybratsche](#): > > the big combat scene at the end of “Severed Dreams”: > > A few times the capital ships rotate in place, without any obvious thrust. Like when they turn to run away, but I think that was merely described in short form, so to speak, to show them ‘turning tail’ after Delenn’s threat. 😃 ---
**Author:** ![Boyo\_Jim](https://avatars.discourse-cdn.com/v4/letter/b/87869e/32.png) [@Boyo\_Jim](https://boards.straightdope.com/u/Boyo_Jim)\ **Post date:** [October 13, 2016, 8:06pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/17 "2016-10-13T20:06:35Z")
> [@lazybratsche](#): > > … A few times the capital ships rotate in place, without any obvious thrust. Between scenes, they somehow end up stopped or traveling in different directions. If you want to be generous, you could say that there are either invisible reverse thrusters, or that all the pitch-and-burn deceleration happens off camera. Still, they’re doing their best boat impression, where they appear to trade shots while puttering around at 20 knots. … Never seen the show or watched any of the battles, but a ship with large enough gyroscopes could rotate without external thrusters. If their thrusters are powered while they are rotating with gyroscopes, their direction of advance would also change. ---
**Author:** ![carnivorousplant](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/carnivorousplant/32/3563_2.png) [@carnivorousplant](https://boards.straightdope.com/u/carnivorousplant)\ **Post date:** [October 13, 2016, 8:13pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/18 "2016-10-13T20:13:52Z")
In these space battles, was everyone oriented in the same way along the Y axis? ---
**Author:** ![HookerChemical](https://avatars.discourse-cdn.com/v4/letter/h/278dde/32.png) [@HookerChemical](https://boards.straightdope.com/u/HookerChemical)\ **Post date:** [October 13, 2016, 8:58pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/19 "2016-10-13T20:58:36Z")
> [@GreenWyvern](#): > > _Downbelow Station_ (which won the Hugo Award for best novel) is the first and most essential book for that universe. This was the first book that came to my mind. The travel between systems is “unreal” (meaning faster-than-light), but the combat is all sublight with distances between ships exceeding light-hours in some cases, IIRC. ---
**Author:** ![Sage\_Rat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sage_rat/32/399_2.png) [@Sage\_Rat](https://boards.straightdope.com/u/Sage_Rat)\ **Post date:** [October 13, 2016, 9:01pm UTC](https://boards.straightdope.com/t/real-physics-in-space-battle/768418/20 "2016-10-13T21:01:58Z")
I think there was an anime which noted that the propulsion that the ships was using was basically more powerful than any other weapon that you could realistically strap onto the ships, so redirecting your exhaust at your enemy was the key to walloping them. But I think that, ultimately, by the time we’ve got realistic intergalactic travel, if we haven’t genetically engineered ourselves to be less warmaking, we will at least have invented new ways of destroying one another. Battle may be all about throwing off a ship’s navigation so that it flies into a star or opening a wormhole near it, such that projectile physics and relative position are irrelevant to what is going on. [Next page](https://boards.straightdope.com/t/real-physics-in-space-battle/768418.md?page=2)