There are two factions here.
One is science fact for which we hold the likes of Neil deGrasse Tyson in high regard.
The second is science fiction. Here I hold me in high regard – modesty notwithstanding.
To be really fair, I tend to write science fiction with a splash of fantasy but without dragons and stuff. These are things I like to leave to others. Princesses? Well, OK, but not as such - they are more your average stunning and curvaceous beauty.
How much science fact is there in science fiction?
Honestly?
Not much, really. To be brutally honest with you, the only real science fiction that became science fact was Arthur C Clarke’s idea for orbital and geostationary satellites.
Yes, I am aware that there have been odd things that come up from time to time. People in ‘Star Trek’ wandering about with iPads, for example, spring to mind. There are lots of others but these are not science fiction ideas becoming science fact on the grand scale of things.
Let’s look at a couple of common ones, ones that I have used as well as several other writers. This is an excerpt from “The Adepts: Book 3 – Pitch Perfect”:
“Robinson heard the crack as the lock failed. He dropped his broom and looked towards the main door - eyes wide in panic; he was too late. The outer cargo doors snapped open, the rush of air swept Robinson out into vacuum. Instantly, the blast doors slammed shut to prevent the ship decompressing. He was caught by the lower legs. The pain coursing up his body was like liquid fire engulfing him. He had a brief moment to see the stars burning brightly against the blackness of space before his eyes froze over and boiled off; then the blood in his body also boiled and shut down his brain functions in one overwhelming burst of agony that took the rest of his life to dissipate.”
This is, of course, arrant nonsense. It is used solely for ‘dramatic effect’ as most things in science fiction and fantasy are.
Let’s look at the truth.
One of the hardest things to do in space is getting rid of heat. Why? Because there is nothing to take it away. No air for convection and no metals for conduction. The best you could hope for is to radiate the heat away. A big risk with space ships is overheating.
This means that the likelihood of your eyeballs freezing over is nil – in the short term, anyway.
What about your blood boiling? Unlikely. Your skin is pretty tough so although the external pressure drop would cause the boiling point of the water in your body to become zero degrees centigrade the skin will prevent the pressure in your circulatory system from dropping too much. Your skin will prevent your blood from boiling off. In any case, you also can’t get rid of the heat so it won’t freeze.
It is possible that the water on your tongue might evaporate off and, likewise, your eyes might dry out a bit unless you keep them shut.
So what is it that will kill you?
A diver coming up from depth, having been breathing pressurized air, will require to breathe out all the way to the surface to prevent his lungs bursting. In this way you might find that holding your breath in space is a bad idea. With no air to replace that expelled you will find yourself de-oxygenating fairly quickly. Once all the air has gone from your lungs there will be a pause of around 12 to 15 seconds (which is how long blood takes to get from the lungs to the brain depending on heart rate – pulse. This is likely to be quite rapid given the circumstances!) and then the brain de-oxygenates. It is all downhill from there.
Sadly, there is no freezing, shrivelling up or exploding going on. People and animals have survived decompression to near zero pressure for sustained periods with no ill effects.
Sorry.
Weapons. Oh, dear. We could go on forever about this.
In “Deep Space Squadron” I wrote about the vibration felt through the hull from the recoil of the great guns on the battleships. Realistically, this is not going to happen with ‘speed of light’ weapons.
Consider ‘laser beams’ as we see on ‘Star Trek’ and such. Lasers do not, in reality, require much energy to produce; they are focussed light beams. Yes, we use lasers to remove hair and tattoos but they really only warm the skin a bit. Destroying a battleship – or even a rowing boat, with one is hardly credible.
I have heard the argument about ‘particle beams’ but even those are massless quantities because they are travelling at the speed of light. If they had mass, according to Einstein, they would be unable to travel at ‘C’ (Speed of Light = C).
My excuse, in ‘Deep Space Squadron’, is that the plasma guns are using explosive gasses to hurl the projectile ball out of the cannon barrel, which is there solely to focus and accelerate the plasma ball. It is the explosive gasses that create the ‘recoil’.
Similarly, the Payan Warriors in “The Adepts” series use a small pistol that throws energy in a similar fashion. It takes a while to ‘charge’ because the gasses needed to hurl the ‘bolt’ have to build up in the chamber; because, in both cases – the Battleship cannons and the pistol, the plasma has an innate desire to remain stationary the force required to push it out of the barrel is considerable. Hence, recoil.
In practical terms, the best weapons for use in space are still solid projectiles – torpedoes, cannon balls and such. Or, as in “Deep Space Squadron”, spare asteroids!
Let’s look at manoeuvring.
In “Crater” and my other ‘space operas’ there are spaceships. These are, in some cases big. Huge, even.
The Battleships and Heavy Cruisers are twelve to fourteen kilometres long. In “Crater” the enemy has a thrust nozzle cluster at the back which somebody remarks is “...the size of Spain!”
In terrestrial terms a long ship like a fuel tanker can take twenty miles to stop. The engines are not very powerful. They also take fifty miles, in some cases, to turn completely around.
Why?
The stress loads on the hull are huge once you start diverting it from its straight path. The tanker wants to bend in the middle, something the designers have not intended it should do.
For this reason there are strengthening factors built into the hull to counter ‘manoeuvring stresses’.
Aeroplanes, too, have their problems in this regard. Aeroplanes (‘airplanes’ in the US where they have their own vernacular) need to be as light as possible; weight is the enemy of flight. And yet they need to be swung around in the air. Small aircraft are easier, big aircraft need strengthening to prevent them from breaking up in flight.
Vast spaceships will also try to bend if they are steered in too tight a circle. It is also wise to bank the ship so that the direction of turn keeps the turning forces along the stress lines of the craft where it is designed to take the loads.
Things are not quite as they seem in science fiction.
Another thing about space ships.
I like to use ‘foldspace’ to go faster than light.
‘Faster Than Light’ (FTL) is a dream that is unlikely to be fulfilled in the near future unless someone comes up with a theorem that disproves Einstein!
So, we pull two parts of space together and slide from one part to the other. This uses huge amounts of (nuclear) energy.
Problem.
Small ships need to go very fast – probably about 0.6C, to go into fold or the front will enter the other part of space so far ahead of the back of the ship that the whole thing will be pulled apart. Very bad for the crew, that.
Some commercial freighters try to do it slower to save fuel but the effect of even a small reduction of speed is to distort the hull, weakening it disastrously.
To get up to 0.6C takes a lot of fuel. A lot!
Now think of a Battleship or Heavy Cruiser fourteen kilometres long.
Minimum transition speed into fold will be along the lines of 0.75C. Accelerating a mass of that size to that speed will take an enormous amount of fuel. They definitely need civilian charter tankers around!
We say we write science fiction or fantasy but, for the most part, science fiction is fantasy.
It is just as much fantasy as A.A.Milne’s ‘Christopher Robin’ who was very, very sick. Milne wrote that “Christopher had gone down with Alice...”
An old form of AIDS, perhaps?
Damn! I’m fantasizing again!
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