On the physics of space battles
Joseph Shoer looks at some of the uncomfortable science behind these science-fiction mainstays:
Explosions are basically a waste of energy in space. On the ground, these are devastating because of the shock wave that goes along with them. But in the vacuum of space, an explosion just creates some tenuous, expanding gases that would be easily dissipated by a hull.
Better choices for weapons include radiation, lasers and old-fashioned bullets. But don’t expect fast-and-nimble dogfights, because steering a ship in space is laborious. With no atmosphere to cut against, changing directions takes time and lots of fuel.
The z-axis fighting we’ve recently come to embrace — the new Star Trek did it a lot — only makes sense in certain circumstances. Orbiting a planet, things get flat again:
The marauding space fleets are going to be governed by orbit dynamics -– not just of their own ships in orbit around planets and suns, but those planets’ orbits. For the same reason that we have Space Shuttle launch delays, we’ll be able to tell exactly what trajectories our enemies could take between planets [...] So, it would actually make sense to build space defense platforms in certain orbits, to point high-power radar-reflection surveillance satellites at certain empty reaches of space, or even to mine parts of the void. It also means that strategy is not as hopeless when we finally get to the Bugger homeworld: the enemy ships will be concentrated into certain orbits, leaving some avenues of attack guarded and some open.
In writing your space epic, do you even need to worry about any of this?
Only to the degree your viewers will.
Each movie and TV series establishes its own level of plausibility, and as long as it plays within that range, audiences are largely satisfied. Space in Apollo 13 is nothing like space in Star Wars. A viewer who complains too much about the Millennium Falcon’s propulsion system will be justifiably shunned.
A general rule for screenwriters is to stick with genre conventions unless there is a story benefit to changing them. For example, in modern space adventure movies you get artificial gravity, warp drive, and shields for free. You can roll your own if it suits your story, but that screen time is likely better used in service of your characters and plot.
(Thanks to Nima for the link.)
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December 17th, 2009 at 11:41 am
I guess I could call attention to Rob Lowe’s line in “Thank you for Smoking:
“It’s a good thing we invented the thing that allows them to smoke in space.”
SciFi means you can throw in a few well-placed theories mixed with a little wishful thinking. Et voila, you fly different than Asteroids.
I’m actually working on a GIGANTIC galactic war, but it’s really a romantic dramedy.
December 17th, 2009 at 12:06 pm
The reimagined Battlestar Galactica did a very good job of portraying space in a relatively realistic way, I found; the way ships maneuvered was well thought out. More and more shows tend to be playing to people that like to have a little bit of reality included with their green-skinned chicks (witness Star Trek, where we follow a crew member being sucked out of a hull breach; the sound goes from chaos and noise in the presence of air to an absence of sound as the shot moves into vacuum – a really impressive bit of work by the audio team, I thought). Both stay in the range that previous SF has established, but they add a new level of believability to the equation that, to me, made them stronger.
December 17th, 2009 at 1:30 pm
I still believe that one of the most physically correct sci-fi films is 2001: A Space Odyssey. There’s simply NO sound in space.
December 17th, 2009 at 2:19 pm
Genres evolve for sure. I actually think it would be a really cool movie if it all took place in zero gravity with space ships moving around like the old video game Asteroid, where it was hard to maneuver. Think if Aliens had all been zero gravity. Filming it is another matter, though.
December 17th, 2009 at 2:22 pm
Forgive this pedantry by a former physicist (MA Oxon 1979) but, strictly speaking, all those battlestars, deathstars and massive space warships we see in movies are invalidated by Lanchester’s equations (notably exploited by Admiral Nelson more than 100 years before they were formulated) which state that an attacker’s firepower advantage is proportional to the square of the ratio of units. So if I was going to field a spacefleet, I’d go for a whole swarm of nimble destroyers rather than one big mutha. Of course, it’s always possible to cobble together some convenient pseudo-physics to explain why the big warships are there – though maybe Lanchester appeals on some deep level to storytellers too, because they’re usually only there to end in a big explosion.
December 17th, 2009 at 2:25 pm
@Sarah – you make a good point about that element of space. It’s SO quiet. ALIEN makes good use of that with the opening, as does the opening of MOON. Space is like one, big, dark back alley with something – anything – just waiting to jump out. So cool.
But back to the explosion thing. John’s right here – no one blinks at an explosion in space even though the science is all wrong.
But @ Tony, you make a great point that real science and physical laws (or some variation therof) can point you to fantastic effects and ideas that just defaulting to the old sci-fi standbys won’t get you.
December 17th, 2009 at 3:01 pm
I propose that there’s an “uncanny chasm” for physics in fiction.
Anything goes if it’s Star Wars where are forms of life are nearly human-scale and the viewer hears the sounds of weapons & explosions in the void of space. The laws of science universally fail to apply to Star Wars.
On the other end of the spectrum is Contact. Written by notorious physicist Carl Sagan, every detail of the science is correct.
Where can things go wrong? When you’re making a point about science in one scene then break all natural laws in the next. As a point of reference: Armageddon.
December 17th, 2009 at 3:02 pm
Good timing. I’m currently reading Insultingly Stupid Movie Physics. Don’t underestimate explosions in space. No, not for the shockwaves, but for the debris that they will send flying at high speeds in every direction.
December 17th, 2009 at 3:51 pm
I think this post addresses the difference between science fantasy and science fiction. Not surprisingly, science fantasy is most of what is written. The only real difference between Star Wars, Star Trek, Doctor Who and Battlestar is the degree of believability. But they are all science fantasy. I also realize that the world at large will always call these types of stories sci-fi anyway. And that’s fine, the audience doesn’t really need to quibble about the terminology. We, however, do need to know which genre we are working in.
December 17th, 2009 at 6:15 pm
I love space battle explosions. They look cool.
I just read a book where an internal explosion caused a space ship to roll (unlikely, but I could come up with a wacky explanation). Then, the ship STOPPED rolling for no reason other than it made it easier for a character to fly by and inspect the damage (damage which wasn’t consistent with my wacky explanation). The story could be applauded for its wacky physics when it made the story unique and the characters were confounded at the right moments, but not for throwing out “an object in motion stays in motion” for no reason.
December 17th, 2009 at 6:32 pm
We have just folded space from Ix. Many machines on Ix. New machines. Better than those on Richesse.
Say what you will about Dune, the movie, but the author of the book managed to show a culture profoundly affected by the vicissitudes of interstellar space travel.
Who can say about faster than light travel? Would there be sound? FTL travel implies time travel. If an FTL drive sent a spaceship back to the early universe era before the decoupling of matter from light, all of space would be brilliantly lit and ringing with sound.
December 17th, 2009 at 6:36 pm
Sorry guys I hit the send button without completing the email line. Here’s the post again. Please delete the previous one if you’ve posted it.
“We have just folded space from Ix. Many machines on Ix. New machines. Better than those on Richesse.”
Say what you will about Dune, the movie, but the author of the book managed to show a culture profoundly affected by the vicissitudes of interstellar space travel.
Who can say about faster than light travel? Would there be sound? FTL travel implies time travel. If an FTL drive sent a spaceship back to the early universe era before the decoupling of matter from light, all of space would be brilliantly lit and ringing with sound.
December 17th, 2009 at 7:03 pm
There are quirky areas of physics being explored today that will no doubt be exploited in some way in the future that will be entirely magical to our present minds. So all this about physics is based on an incomplete knowledge of right now. It’s about like people one hundred years ago looking towards now. Most predictions were way off because the human part of things was neglected. Humans are really a lot less predictable in some ways and more so in others than they like to think.
What matters to me is if there’s a coherent world being created right then and there on screen for me. The Fifth Element did that for me. I bought everything because it was stylistically synchronous and the people within didn’t act weirded out by anything, but all that would weird out the audience was greeted with expectation and familiarity by the cast. Bruce Willis, Brion James, etc. all acted as though everything their character was encountering was perfectly within their capabilities of dealing with. The cast individually and collectively buys into the world they are portraying, I buy into it as an audience member.
December 17th, 2009 at 8:27 pm
funny Star Treck is coming up here. Those are not good movies, but mainly fan-based. As transformers are moving in that direction too. however, transformers has many fans. Sounds in space is about what is trendy at the time the movie comes out. I say no more… I watched a really cool avatar trailer today!! With the too close up fighting scenes from transformers more slick made. I hope the movies for kids trends fades away fast. avatar looks like a movie for 14-year olds. Cameroon used the same line as mr lucas “i waited 15 years to make this… so the technology could make my dreams come alive” maybe not a presise quote. and i feel bad about bashing his… no i don`t!
December 17th, 2009 at 8:34 pm
ok, this is a great one: one arcitect, designing houses, stated he spent 30 years learning about fitting frames in relation to what experience the finished product looked like. many directors may not know that.
December 17th, 2009 at 11:43 pm
Most downbeat space-combat ever: The Forever War, by Joe Haldeman.
Humanity’s ships have all the thrust they need coupled with a complete lack of artificial gravity, so that the only way for the crew to survive the necessary maneuvers is to dose themselves out and take a nap in some kind of g-tank. But that’s OK, because the relativistic impossibility of tracking an incoming projectile the size of a grape traveling at 0.5c makes human reaction times useless. The best the crew can do is dial a bunch of probabilities into the computer, go to sleep, and hope they wake up. This also makes it easier to vent the ship’s atmosphere so as to prevent the ship from tearing open like a pinata should one of those grapes actually hit.
It’s terrifying, presents extreme challenges to spacefarers involved, makes you think, and is about as cinematic as watching your dog take a dump.
December 17th, 2009 at 11:45 pm
How the hell does ‘projectile the size of a grape’ sound so much smaller than ‘bullet’?
December 18th, 2009 at 1:17 am
@ Graham,
Because of associative reasoning.
The bullet’s associated target is a human heart. – A 9 ounce piece of meat. – The NASA grape-of-destruction is taking out an international space station weighing ummm… 227 metric tons & killing 3 people in the process. – Proportionally, the grape is doing 554,000 times as much damage per millimeter as your bullet. (So long as you’re sticking to the classics and using a 9mm Beretta & a pinotage grape @ about 16mm)
The bullet is only addressing 1 oz of target per millimeter of mass. (And killing .11 unfortunate people per mm to boot.) — The grape however, it rupturing 554,000 oz of target per millimeter… and killing .18 people to boot. :)
December 18th, 2009 at 12:04 pm
Nicely done Synthian.
One thing that always got me was how when two spaceships rendezvous at a particular point in space after having travelled many light years from different regions they always arrive oriented on the same axis. Unless the universe has a universally understood top, bottom, left, and right, surely one of them us going to arrive upside down at least once.
December 18th, 2009 at 12:16 pm
this is really good nerd behaviour. I calculated i need to write Synthians 18, in line post down to handlable paper. And read it infront of a mirror, out loud 10 times. and the lay down and rest for 30. then repete the sequense to the extent i know it by heart and randomly spit the post out at cool bubling parties, and cheer big smiles after.
December 18th, 2009 at 12:43 pm
The show “The Universe” on History channel had an episode earlier this season called Space Wars. They showed how a space battle might really look in comparison to the typical Star Wars type battles.
They showed 90 degree direction changes, fighter ships using a cube like design and lasers that would create a solid line from the attacking ship to the target. (instead of a laser bolt) It was pretty cool if you’re looking ideas for a sci-fi script.
This goes for lying in general so I’m assuming it will work in sci-fi. If you’re going to alter reality somehow to fit your world, make sure your lie is accompanied by some truth.
The audience should be able to suspend their belief across that lie if they have a solid foundation of truth on either side.
December 18th, 2009 at 5:42 pm
if you introduce a character in full too soon, the audience will fall in love with it or reject it in lack of tention.
December 18th, 2009 at 6:00 pm
Sarah (#3) mentioned 2001 being very accurate — which is right on except for the scene when Dave flies back into the ship through the airlock. (After HAL won’t open the pod bay doors…) Before being exposed to the vaccuum of deep space, he takes a breath — which is apparently the worst thing you can do because your lungs will rupture. Best bet is to exhale.
The insanely underrated movie Sunshine had a harrowing similar scene that, if memory serves, was done accurately.
December 18th, 2009 at 7:34 pm
I hope event horizon is not accurate. Those guys at Cern can be really scary if they have the same mindset as scientists does. They give it away. Whatever technology they find.
December 18th, 2009 at 7:47 pm
Brings to mind another interesting geek-read: http://blogs.discovermagazine.com/cosmicvariance/2009/05/14/rules-for-time-travelers/
December 18th, 2009 at 10:25 pm
those rules are silly. go to michaelbay.com if you want the coolest job in the world right now.
December 18th, 2009 at 11:50 pm
@ Joshua,
I am now having le cafe-press T-shirt made that says:
“You can’t travel back to before the time machine was made unless you want to go to a parallel universe, in which case you’d better be ready to kick your own ass.”
December 19th, 2009 at 7:31 am
They did that in “the one”. that one was super exciting. (removed genius line here) hey Synthian and Josh. What are you guys writing on?? People are so secretive. Am i like the only one here without the wga sertificate…
December 19th, 2009 at 11:29 pm
A children’s tragedy space-opera: “The Little Grape Who Could”.
December 19th, 2009 at 11:44 pm
What I always wanted to know is: What happens to a woman’s cycle once she leaves the Earth/Moon system? Anyone ever do a story about that?
December 20th, 2009 at 1:56 am
too complicated. sounds like Frank is talking justice here. if those guys had sex in space they wouldnt not be able to walk after.
December 20th, 2009 at 11:48 am
could make a needed escape from earth. with some new and exciting plot with humans having to reproduce in space looking for another home. Climate 2009. Just floating in space and no particular battle. Our father don
t say no. But he dont like it.January 3rd, 2010 at 8:45 am
I’ve never known a screenwriter yet who understood the basic scientific fact that in space, no one can hear you explode. But, to paraphrase you, plausibility and suspension of disbelief always takes a back seat to spectacle. And no one wants to hear a silent space battle, although it may be entirely and scientifically factual.
January 4th, 2010 at 9:41 am
I think Starwars is the best space battle series/film ever made. There`s rumors Michael Bay maybe takes his robots to space in TF3. Maybe it will be better
January 8th, 2010 at 10:21 am
I
ve posted alot of comments latly and this forum is so full of my name even Im getting tired. Im gonna have a good 9s sleep and return when people don`t expect it.January 8th, 2010 at 4:41 pm
yeah, one more thing. I`m not trying to be cool or anything. you guys are disney: be nicer.
January 8th, 2010 at 11:48 pm
final attempt and failed. John August has no mercy and hates some of his posters. please, can you erase my posts before i end up dead in a dumpster??
why is is cool to close threads and wait to people get so desperate the site owner deletes his posts that the owner begin liking hating the poster?
I beg you, please John-can you erase my posts?? I will never ever go anywhere near a hollywood site, conversation or anything to do with anything related to anything in LA.
have a heart man. please.
January 9th, 2010 at 3:23 pm
when i woke up it was like knowing it was way better back there and i knew the nightmare was on. there was no transformers. i didn`t date miley cyrus. i was to have so much unsolved pain i had to jump directly to a sigarette i knew soon would take my life away. there was no other option.
January 9th, 2010 at 6:23 pm
i went on the internet today. with all the doomsday motion pictures made the past few years, this had to come up: http://www.youtube.com/badasselvis i guess the dude filming would love, love and adore the attention and channel subscriptions. so do subscribe. i have my theories about what is going on and everybody will not be saved. i had this PERFECT film about the reason-but i guess it will never be made. write fast guys, and have this as the main topic. i`m really looking upfront to have a major fire with all my good, great and maybe not so cool writings about life, love and my personal reflections. good stuff about life. great about love, and …. you guys get the idea.
January 9th, 2010 at 7:06 pm
i recomend not go to panic. but i do recomend having a plan to get out of here without getting burned alive. the vids could be fake. what the hell would i know. in my life, i`m calibrated to be controlled from the inside of my self-as a personal judge. back in the day, some force took me off a cliff and took my body right off it. my back is broken and i could do nothing about it. so NEVER ever trust me.
January 10th, 2010 at 5:41 pm
I found out these are fake for sure, so no space battles at all. He just tries to scare people. I took another look at stranger than fiction today, and tomorrow I
m going to see my lawyer. Is it possible to target spesific stereotypes in a film, and make the wrong advice to them and getting away with it? Maybe Zach Helm just really hates people, i dont know. I guess I would be along the people Zach is going to meet on the other side sending him to hell.January 14th, 2010 at 3:44 pm
or maybe its just rocks. 6000 satelites goes around.
I looked at the denmark ufo report and it sctechy. as the sights are simular. people has reasons like the dog got upset after i got upset. green shading and moved. its like i see most things when i`m most off. and people talks about getting biased looking at objects with no attatchments. i really cant tell for sure.
-sorry zack, its not forcing him to eat them. or who knows. but they can bite. ALOT-
sorry for complaining so much…. I love Hollywood.