Tech Tuesday: Space Travel
Posted by childofthehive | Filed under Tech Tuesday
Space travel is a very common element of science fiction stories but the way that travel is perceived can vary enormously depending on when the story is set. Think of it a bit like crossing the Atlantic ocean. 1000 years ago, crossing the ocean was immensely slow, difficult and dangerous. If you set off, chances were that you wouldn’t make it to the other side. If you made it, you got sagas written about you.
About five hundred years later, there were trade routes being established. It wasn’t fast or comfortable and you might still die in the attempt, but the odds were considerably better that you’d make it to the far side and so it was reasonable to do so for trade and profit.
Then steamships came about in the 19th century. Travel got faster, safer and more comfortable. It could still take months on a slow ship, but might take only a couple of weeks. Luxurious liners made it attractive to cross the ocean for pleasure as well as profit. On the whole, the trips were much safer, but still things could go horribly wrong.
About half-way through the 20th century, passenger planes were becoming much more common. The journey time dropped from weeks to hours and the price has dropped to a point where crossing the Atlantic is a common thing done for business and pleasure by a huge number of people every day.
Translating the analogy to space flight, you have enormous freedom as a writer. You can choose to set your story at any point along this spectrum, from space travel being immensely dangerous to it being so common that you can walk down to your travel agent and buy a ticket to Alpha Centauri.
In some ways it depends whether you want space travel to be the point of your story or something in the background. If the space ship and the journey are the focus of the plot, it would make more sense to set your tale somewhere near the beginning of this timeline, in the same way that a difficult crossing in a sailing ship lasting weeks and full of uncertainty about survival is likely to be more interesting than a story where someone gets on a plane, watches a couple of movies and then gets off at the other side a little tipsy from the free booze. This is by no means a rule (I have read an amusing short story set on an ordinary plane flight) but it’s something to think about.
If you want to write a story about people journeying to other planets, meeting aliens and having adventures between the stars, you’re likely to want to go for the later end of the timeline, otherwise the plot will have to have long pauses while your characters travel.
A possibly interesting option would be to use the idea of relativistic flight to do a mixture. The idea, which I touched on in my post on faster than light travel, is that as you approach the speed of light, time appears to slow down so a travel time of years might feel like days. You could have newer ships being able to get closer to light speed overtaking ships that were built centuries before them.
In short, you’ve got the freedom to let your imagination run wild.
Tags: future, sci-fi, science fiction, space travel, spaceships, technology
Tech Tuesday: Faster than Light Travel
Posted by childofthehive | Filed under Tech Tuesday
When writing fiction, there are few rules but a lot of guidelines. With science fiction, one of those guidelines is to stick within the laws of physics as known at the time of writing. So you can write about things we can’t do yet, but it’s best to make them seem at least feasible within the bounds of known science.
One exception to this guideline is faster than light (FTL) travel.
The speed of light in a vacuum is a universal constant. Einstein’s special relativity theory states that this constant is the highest speed that can be achieved. The actual theory is a lot more complex than that and there are some complications around the flow of time at light-speed. Without getting into the physics in depth, it suffices to say that no matter how powerful your spaceship is, it won’t be able to move faster than the speed of light.
This can lead to problems if your story involves travel between different planets. The problem is simply one of distance. The nearest planet that’s been discovered is 10.5 light years away. So even if you can get up to light-speed, it would take more than a decade to reach it. The planet in question is more similar to Jupiter than it is to Earth, so having humans landing or living on it would be rather difficult. If you want to have human-inhabited colonies and planets spread across the galaxy, the distances are likely to be much vaster. It’s more likely that it would take a lifetime or more to get between planets where we could survive (assuming we find any).
That could be part of your story. There are some very interesting stories written about colony ships travelling to other worlds, using either generation ships or freezing the colonists. There’s also an interesting piece of Einstein’s theory is that as you approach the speed of light, time slows down. So the ship might take years to get there, but it will feel like days or weeks to the travellers.
All of this is interesting fodder for fiction, but there is still an issue if you want your characters to be able to travel around between different worlds regularly. If you want people to be able to set out in a ship and arrive in a few days, then you hit this problem.
You can get round this issue using hyperspace, but that’s another complex theory that’s deserving of a post in its own right.
Or you can cheat. I did say that this was an exception to the guideline about obeying the laws of physics.
Just give your ships FTL engines. Travel between planets is so well-established in science fiction now that readers are willing to ignore the impossibility and enjoy the story. But if you can find a scientific way to justify it, that’s even better.
Tags: advice, faster than light, future, sci-fi, science fiction, space travel, spaceships, technology
