Wednesday, January 28, 2009


As many of you probably know by now, I'm helping to create a new science fiction role playing game. One thing that should be different about this game as opposed to others is that, for the most part, we are trying to use plausible science in the creation of the game. Granted, we are using hyperspace, but who wants to play a game where relativity has to be taken into account? In other ways, we're trying to make it believable. Think more along the lines of Babylon 5 as opposed to Star Wars.

Most of the "encounters" that characters are going to have will be with the major species of the game, but we'd still like to include some "monsters" in this thing. With that in mind, we're wondering about vacuum based lifeforms. What do you think they would need to survive, and how would they have evolved?

Obviously, they need to be able to "breathe" in some completely new way, they need to be able to function in vacuum, they need to be able to survive the extreme temperature fluctuations, they obviously can't have blood like we have...

...what else do you think we need to take into account when we create these critters?


Keith said...

This is a very interesting idea.

First, purpose of breathing is to take in gas, mix with liquid to produce an exothermic chemical reaction. In other words to get energy needed for metabolism and creating biomass.

In a vacuum there must be another source of energy. Water would be in the form of ice. Carbon compounds would be in the form of regolith, basalt, graphite or even diamonds. In space there would be dust, meteors and the tails of comets.

1) Absorb light, heat or other electromagnetic energy (like plant photosynthesis) and use energy to extract carbon and other elements from solids and to melt ice for metabolism.
2) Ingest solid matter (regolith) or other life forms (interstellar plankton) and extract energy from chemical compounds.
3) Collect charged particles from solar wind.
4) Absorb heat from volcanic activity and use to build metabolic chemicals to build biomass.
5) Extract radioactive material from solid matter to fire small fission engines for energy.
6) Natural cold fusion from melted ice with exotic trace elements as catalysts, producing heat.
7) Natural silicon semiconductors with photovoltaic cells driving randomly assembled transistors which have evolved intelligence. (An old story idea - from 1968 - never did finish it, though).

Keith said...

Hal Clement had some great vacuum based life forms on a hot planet that used liquid tin, lead and antimony as a kind of blood. Think of the old marvel metal men comics. (I used to buy them with paper route money and had the first 10 issues.) When the sun went down Clement's aliens froze in whatever position they were in and did not wake up until the next morning.

There is never a true vacuum and there are always limited amounts of hydrogen and other gases, although very rarified. Some heavier gases make hang like a mist over planets or asteroids that have more gravity, even if the pressure is still extremely low.

Liquid water may have some exotic antifreeze compounds to keep it liquid and also to keep it from boiling off at low temps and pressure.

I guess the secret is to have something obvious that doesn't need a lot of explaining. After all this is a game, not an engineering lecture.

Possibly liquid tin instead of blood would be good, because it has a built in vulnerability. Just get the thing in a shadow for a few minutes and it freezes up.

J Erwine said...

Thanks for all of the input Keith. A lot of it I'd already thought about, but you brought up a few points that I will definitely have to keep in mind.