So last week I went on a tear about Star Trek: Voyager. I’ve been catching up on some science fiction and one of my readers pointed out to me that my last post wasn’t very bitter. Actually, they said the same thing about the post before that too. While I find these topics absurd, outlandish, or unfortunate, some argue that they are not bitter topics. So instead I would like to go over something that is both educational and embittering. Let’s talk about why the way we like to think about space travel (at least according to TV, video games, books, etc) is messed up.
I talk a pretty good game about the differences between science fiction and science fantasy, but both are really just differences in narrative technique. Everything in science fiction (at least space operatas) is pretty much fantasy too. There’s a lot of stuff in science fiction we take for granted as totally plausible, even when we should know it’s false.
And it’s tricky. We see stuff like Battlestar Galactic or Star Wars and assume that there are no Wookies in space, Greedo probably wouldn’t have shot first, and hyperdrive isn’t real. But we forget about little details like that there is no noise in space or that we would be weightless all the time. They seem like no-brainer assumptions, but we totally forget they aren’t real because most of us don’t know anything about space. And they make things worse.
Did you know that we pretty much can’t procreate in zero gravity? As a matter of fact, zero gravity breaks down our muscles, weakens bone density, and does whatever it can to kill us.
Not convincing enough for you? Ok, let’s talk about the deadly space radiation out there that is just waiting to get a shot at your healthy cells. Space is just full of it. And it kills if you aren’t careful.
Fine fine. You’re not convinced. Let’s just have kids on planets and wear lead underwear all the time because America can do anything. Alright. Let’s get to it with the REAL problem with space adventure.
Traveling At Light Speed Or Something Like It
*Please note that I am not a physicist, and I don’t work for NASA.
Space is big. Really big. So big, in fact, that even light has trouble getting anywhere in a reasonable time. Light travels at 186,282 miles per second or approximately 670 million miles per hour. That is, literally, an unimaginable speed, but it takes forever to cover the vast distances of space. For example, light spends an average 5.46 hours traveling from the sun to Pluto. And that’s just a planet at the edge of our solar system. So Pluto’s distance is almost 6 light hours from the sun. We measure the distance to other solar systems in light YEARS!
Light speed is also the upper limit at which anything can travel. And by anything I mean light. It’s pretty much a certainty in physics that nothing can reach the speed of light but light, much less exceed it. It’s super complicated, but in layman’s terms (the only terms I’m qualified to speak in) you need something like infinite energy to move an object with mass up to the speed of light. Oh, and as you approach the speed of light, time relative to you slows down. Yes, that means you will age more slowly than the rest of the universe around you and, theoretically, if you reach the speed of light, time will stop.
And let’s not forget the relativistic distortion. Everything looks more and more skewed (as well as slower) as you approach light speed. Things get all bendy and weird and, it’s harder to see exactly where an object is. So if you have two objects moving at high speed it can be difficult for both to see each other. It doesn’t help that moving at high speed changes the perception of other object’s speeds too. In this case high speed is like half the speed of light.
Sorry your sun exploded, but you won't see it until it hits you.
So let’s talk about the distance to Pluto again. Light from the sun takes an average of 5.46 hours to reach the outer edge of the solar system. So if you were standing on Pluto and the sun exploded, you wouldn’t know it for more than 5 hours! Heck, you probably wouldn’t have time to see the explosion, since the light from the explosion would probably be going the same speed as the explosion.
So what does all this garbage mean? Basically that we can’t reach light speed and even if we get close, space adventures won’t look like they do on television. If we want to have a sweet intersystem empire with bases on the moon, domed cities, and terraforming (a la Cowboy Bebop or Firefly) we’ll have to find a way to at least travel at a reasonable fraction of the speed of light for commerce. So if we can get a ship to travel at 10% the speed of light (.1) it could make it from the center of the solar system to Pluto in about 54 hours. That’s if you can keep your crew from becoming a smear on the back wall. If astronauts have trouble handling acceleration just trying to leave Earth, imagine what accelerating to .1 light speed (67 million miles per hour) will do.
Communications in that same intersystem empire would be limited to the speed of light. Conversations from one ship/planet to another ship/planet could take hours or days as one party has to wait for the transmission of his radio signal/laser/whatever communications to reach the other end of the system and then wait the exact same amount of time for a reply to travel the distance back. Not exactly Star Trek.
And space battles would be stupid hard. Space is full of crap we can’t see because it’s too small, too dark, or moving too fast for us to sense. So let’s assume that you could actually see a spaceship from the other side of a solar system (complicated even when you know where/what you’re looking for and it’s lit) and you want to shoot at it. Well if you shoot at it with some kind of projectile like a bullet it will leave your ship at a slightly faster speed than you are traveling. Let’s make this simple. So you’re charging the target at 1 tenth light speed and you shoot a missile. Unless the missile is really awesome, it’s probably going about .1 light speed as well. Unless you are damn close to your target, relative to the size of our solar system, your missile could take hours to get there. And if your target changes speed or course at all you will definitely miss. Please note when you fire weapons in space and miss they keep going and going and going until they hit something 10, 100, or 1,000 years later.
Voyager fires torpedos while travelling many multiples the speed of light with no consequences because Gene Rodenberry can do whatever he wants.
So maybe lasers are the way to go, instead. Well lasers travel at the speed of light, so if you are more than a few light seconds from your target (remember that Earth itself is 8 light minutes from the sun) it will also probably miss. Oh, and because you and the target are moving at such high speeds you probably aren’t seeing where the target actually is or what it really looks like (relativistic distortion + time dialation = boned). And because you and the target are moving so fast it will be impossible for you, a human, to push a button quickly enough to hit it in close quarters. Odds are even if you did hit the target the impact would happen to fast too see.
So why am I so bitter? Because all of scifi ignores these rules. Yes, you can cheat some of the distances to other star systems because it’s science fiction, but these are very real constants of space travel. Every show should have to deal with this. Remember when the Death Star blew up Alderaan, and it was super fast? Light shouldn’t travel to a target so quickly unless you are really close to it. And since the planet blew up and they were fine I have to assume they were far away. And look at Star Trek. It should take forever for any ship to contact Star Fleet Command, much less actually fly from Earth to any planet in the solar system, even if it’s close.
That took about 1 second to leave the Death Star and destroy its target. So the Death Star ought to be no more than 186,000 miles away. Pretty close to an exploding planet for them to not have any problems.
Everything about space should be slower, more boring, and more complicated than it actually is. And unlike relationships, wars, and car racing, because the average human knows next to nothing about quantum mechanics or space we all see this stuff and assume all but the most obvious parts are real.
If you want to read a scifi series that tackles some of these mechanics, check out Dauntless by Jack Campbell. Then again, if you want a book that has likable characters maybe just watch Farscape reruns and forget everything you read here.
I would suggest this book as well.
http://www.amazon.com/Starfarers-Poul-Anderson/dp/0312860374
Good article. The relativistic nature of velocity and the speed cap of c is…. awkward. Because I’m a total physics nerd, I was curious as to how long it would take to travel from the Sun to Pluto when taking acceleration and deceleration into play.
If you were to accelerate at one earth gravity (1g = 9.81 m/s^s) it would take 17.96 days in a straight shot… which is an impossibility due to orbital mechanics. You’d actually have to plot a much longer, parabolic route to intercept Pluto… and I didn’t want to try to calculate that.
Oh, and you would reach a peak velocity of 0.025c. At 1g acceleration, it would take a total of 35.38 days to reach 0.1c (which means it would also take that long to stop).
And then things get REALLY complicated once you start talking about sensors and reaction times. When you are moving at 0.1c, you don’t have a lot of reaction time for course corrections and emergency manuevers. That’s one of the reasons why the pilots needed Spice in the Dune universe: so they can see far enough into the future to make intelligent navigation decisions.
If the speed of light really is a cap to velocity… I’m seriously not sure how we can ever hope to have a multi-planet empire or explore the stars. The cosmos are just waaaay to damned vast.
Thank you for mentioning Dune. You are my hero for the day.
That is a really good point. I wanted to touch on acceleration and time distortion more, but I was already pushing 1500 words. I’m really glad you brought this up though. Star Trek cheats with inertial dampeners (so acceleration doesn’t kill everyone) and what appears to be near infinite fuel for sub-light and light speeds. We probably won’t have those luxuries and if we do I honestly have no idea how we’ll avoid blowing each other up first.
I skirted the issue of interstellar travel because people always talk about wormholes or transiting into quantum space or alternate dimensions. But if we do actually have to travel below the speed of light to get to other star systems, we are basically boned. Once you go to Alpha Centari or wherever you want you’re pretty much on your own.
I think the implications for human society would be very strange You would have a few (and maybe someday a lot) of segmented sections of space where people are there, but they don’t talk to their interstellar neighbors. And if you did do something like The Forever War, people will basically leave for space from home and never come back.
I suppose the upside is that Aliens are also bound by these rules and have way less incentive/means to put the hurt on us.
P.S.
What’s Dune?
For physics at the end of the year we had to do calculations where you’re traveling at .99x the speed of light and how does time change and stuff. It was rough, because either you can fathom it or you can’t, and then no formula can help you.
Allow me to respectfully disagree and say that I think you’re taking the right approach. All the things you say about physics and the speed of light, etc… are quite accurate (I studied physics, so it sounded quite familiar), but I don’t think the point of fiction is always to be accurate. Have you heard of the distinction between hard science fiction and soft science fiction? Hard sci-fi is usually quite scientifically accurate and plausible, whereas soft sci-fi is is more like fantasy. The point of it is to suspend disbelief and tell a story. Of course it’s nice to have some meticulous, scientific sci-fi sometimes, but sometimes the story requires the spaceship to travel at the speed of light, and I”m fine with that, as long as the story that’s being told is worth it. I think there’s room for both fantasy-esque soft sci-fi Star wars and the hard sci-fi Dauntless in the world.
p.s. Dune is a science fiction novel by Frank Herbert (with several sequels), which is considered to be a “classic” of science fiction. I could go on and summarize it, but wikipedia would do a better job.
He knows what Dune is, I think he put that in there for my benefit. Grrrr.
I tend to agree with you. I think my concern is that all of popular Scifi is soft. If hard science is entertaining and education (like vegetables are delicious and good for you) and soft science is candy, I’m inclined to believe we are getting too much candy. Not that there’s a lot we can do about that since candy sells.
And because people (like me) don’t know anything about space we can easily assume what we are seeing is at least partially true.
Also, I’ve noticed that Star Trek, the staple of science fiction television, has not aged well in terms of tech jargon. Sometimes people on Voyager say things and I’m like “That is totally not real and you probably could have come up with a better way to lie abou it.”
Oh, and I do know what Dune is, but I haven’t read it. I just like to poke at things TJ loves.
But John, Star Trek battles didn’t take place across Solar Systems… Remember when the Federation was like 25 on 1 vs. that Borg mothership in First Contact? Relatively close quarters (Like an area the size of Texas… cubed…)
AND, if you DID manage to reach the c, it wouldn’t take any time at all to get places! Time stopped, remember?
I know I know, time would stop relative to “idle”… But what the hell constitutes “idle?” Every piece of matter in space is in motion, and at drastically different speeds.
Further, What if I were on that ship as it were going the speed of light, and I got up and walked forward down the aisle to take a tinkle (pretend we have gravity for a moment). Am I going faster than the speed of light? I’m moving forward relative to an object going the speed of light… Right?
Your points are accurate, however there are explanations for several of the problems you pose in Star Trek at least. The whole idea of the Warp drive is to warp the nature of time/space just enough to cheat the rules of traditional physics. In fact that’s what the arching symbol represents: the idea that the warp bubble gets you past the infinite energy needed to achieve light speed (read Star Trek Federation for more on this). Artificial gravity plates are what keep people walking. On multiple occasions of the shows/movies they have failed and people will float around weightless. And we’ve all heard the phrase “inertial Dampers” and probably never thought about it but it’s supposed to be technology that dampens the effect of inertia so that the crew doesn’t become a smear on the wall when the ship accelerates.
Of course all of this is fantasy technology, but it’s also an attempt to address the issues you raise in your article. If mankind is going to explore space those kinds of technologies would have to be invented first.