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.
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.
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.
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.