29 February 2012

Survival geology for the space traveler

Posted by Jessica Ball

Image from NASA/JPL-Caltech

For your reading pleasure: a totally frivolous post based off musing I’ve been doing when I actually have time to sit down and watch TV.

Recently I’ve been on a scifi kick (and got sucked into watching episodes of Stargate: Universe online, which is a great way to see a whole series but a massive free-time sink). Interpersonal issues aside, the characters on SGU, who are stuck on an alien spaceship on the other side of the universe, spend a lot of time visiting new planets, looking for resources like food and water. Sometimes the main barrier to this is an alien critter that doesn’t like them much, but often they end up on deserted planets with little more than a “well, you can breathe and it’s not too cold” from the probes they send through first.

This seems like an awfully dangerous way to go about things, even if you have a remote control camera to send through your alien transportation device of choice. Wouldn’t it make a lot more sense to do some kind of triage before you go traipsing around a new planet, hoping to stumble across the resource you’re looking for?

This got me thinking about how I would handle things if I were the ship’s geologist. (It would be really cool if that was an attainable job description, but we can’t all be astronauts, I guess.) In a situation where making a mistake might lead to unpleasant consequences, it would be a good idea to do the same methodical check each time you’re thinking of visiting a new planet. So here are a few things I would pay attention to after my initial “Holy crap I’m going to another planet!” moment, assuming I had the sensors to pick up data like this:

  1. What does the atmospheric composition look like? Does it have a lot of greenhouse gases (probably a hot climate below) or is it pretty thin (cold, unbreatheable or both)? Does it protect the planet from bombardment or space weather? It’s great to find a planet with useful resources, but not if you’re going to be crisped by radiation before you get to them.
  2. What’s the planet’s composition? This is going to affect important things like gravity. Just because your planet is the same size as Earth doesn’t mean it will have the same composition and density – so you might be learning to moon-walk faster than you thought.
  3. Does the planet have active tectonics (and can you tell from a visual analysis)? This makes a big, big difference. Not only would this mean a higher potential for natural disasters of all types, but it will also result in a much more diverse planetary surface, and possibly different climate zones as well. (A planet without tectonics can still have volcanic activity, though.)
  4. Does the planet have liquid water? This also requires you to pay attention to the surface temperatures. An icy planet could still have water, or it could have methane snow (not very palatable). There are also a lot of other liquids that look like water but aren’t going to do you much good. (I will give the SGU crowd credit on this one – they do a lot of chemical testing when they’re looking for potable water.)
  5. What resources are you looking for? Carbonate rock might be good for fixing your air filters, for example, and could also contain useful things like flint nodules. Heavy metals can be used to fixing electronics, and are more likely to show up in mineral veins in plutonic settings. Clays are more likely to show up in tropical or volcanic settings. Knowing where you’re likely to find springs (like in karst topography) will save you time if you need water.
  6. What are the hazards? Are you parking your shuttle near an unstable edifice, or on a river floodplain, or next to a volcano with recent eruptive deposits? Are there visible fault scarps? Do you see evidence of flooding or tsunamis?
  7. What’s the likelihood that you’ll find something edible? Chemistry aside, most plants (and the animals that eat them) want to live in settings with nutrients available, which usually means you need soil of some sort. Extremophiles do exist, but they’re also likely to be unattractive, inedible or downright poisonous, depending on how they’ve adapted to living in their environment. Don’t take the chance that you might actually find arsenic-based life.

Assuming the landing party makes it down to the planet in decent shape, doesn’t get eaten immediately by an alien dinosaur or attacked by carnivorous plants, and has a little time to look around, here are a few other tips:

  • Some clay can be used as a filler in food, so if you need to stretch your rations, tell your geologist to look for kaolinite. Makes a great face mask and sunscreen, too.
  • If you’re near a volcano and there are fumaroles around, sticking your face in them and commenting on how much they stink is probably a bad idea. Hydrogen sulfide is detectable at very low concentrations, but if it gets a little more concentrated it will likely kill you. Also, carbon dioxide likes to hang out in those places too – and you can’t smell it.
  • Try and carry some dilute HCl around with you – it’s really handy for finding those air-scrubber-worthy carbonates.
  • Rocks don’t care that you’re down to one shuttle that’s held together with spit and duct tape. If you crash it in a quarry (or other similarly rocky place with steep sides), rocks are going to fall on it.
  • No, you cannot create a cannon with coal, sulfur and diamonds. (To start with, you need charcoal, not coal. Also, potassium nitrate doesn’t occur naturally takes a little effort – you’ll need to go find a big pile of animal manure and do some processing, or stumble across a mining operation.) If you’re about to be attacked by something, just throw the diamonds at it – Β it will be much more effective in the short term. (Okay, this one is from Star Trek, but it’s just as applicable.)
  • Please boil your water. Or throw some iodine in it. It might save you trouble later on.

All right, wannabe space travelers, what geological advice would you have for someone about to set foot on an alien planet?