Энди Вейр - The Martian

There are four different safety interlocks that prevent the regulator from letting the Hab’s oxygen content get too low. But they’re designed to work against technical faults, not deliberate sabotage (bwa ha ha!).

Long story short, I can trick the regulator in to pulling all the oxygen out of the Hab. Then I can wear a spacesuit (so I can breathe) and do whatever I want without fear of blowing up. Yay!

I’ll use an O2 tank to spray short bursts of oxygen at the hydrogen, and make a spark with a couple of wires and a battery. It’ll set the hydrogen on fire, but only until the small bit of oxygen is used up.

I’ll just do that over and over, in controlled bursts, until I’ve burned off all the hydrogen.

One tiny flaw with that plan: It’ll kill my dirt.

The dirt is only viable soil because of the bacteria growing in it. If I get rid of all the oxygen, the bacteria will die. I don’t have 100 billion little spacesuits handy.

It’s half a solution anyway.

Time to take a break from thinking.

Commander Lewis was the last one to use this rover. She was scheduled to use it again on Sol 7, but she went home instead. Her personal travel kit’s still in the back. Rifling through it, I found a protein bar and a personal USB, probably full of music to listen to on the drive.

Time to chow down and see what the good Commander brought along for music.

Disco. God damn it, Lewis.

Well I think I’ve got it.

Soil bacteria are used to winters. They get less active, and require less oxygen to survive. I can lower the Hab temperature to 1C, and they’ll nearly hibernate. This sort of thing happens on Earth all the time. They can survive a couple of days this way. If you’re wondering how bacteria survive long periods of cold on Earth, the answer is they don’t. Bacteria further underground where it was warmer breed upward to replace the dead ones.

They’ll still need some oxygen, but not much. I think a 1% content will do the trick. That leaves a little in the air for the bacteria to breathe, but not enough to maintain a fire. So the hydrogen won’t blow up.

But that leads to yet another problem. The potato plants won’t like the plan.

They don’t mind the lack of oxygen but the cold will kill them. So I’ll have to pot them (bag them, actually) and move them to a rover. They haven’t even sprouted yet, so it’s not like they need light.

It was surprisingly annoying to find a way to make the heat stay on when the rover’s unoccupied. But I figured it out. After all, I’ve got nothing but time in here.

So that’s the plan. First, bag the potato plants and bring them to the rover (make sure it keeps the damn heater on). Then drop the Hab temperature to 1C. Then reduce to O2 content to 1%. Then burn off the hydrogen with a battery, some wires, and a tank of O2.

Yeah. This all sounds like a great idea with no chance of catastrophic failure.

That was sarcasm, by the way.

Well, off I go.

Things weren’t 100% successful.

They say no plan survives first contact with implementation. I’d have to agree. Here’s what happened:

I summoned up the courage to return to the Hab. Once I got there, I felt a little more confident. Everything was how I’d left it (what did I expect? Martians looting my stuff?)

It would take a while to let the Hab cool, so I started that right away by turning the temperature down to 1C.

I bagged the potato plants, and got a chance to check up on them while I was at it. They’re rooting nicely and about to sprout. One thing I hadn’t accounted for was how to bring them from the Hab to the rovers.

The answer was pretty easy. I put all of them in Martinez’s spacesuit. Then I dragged it out with me to the rover I’d set up as a temporary nursery.

Making sure to jimmy the heater to stay on, I headed back to the Hab.

Buy the time I got back, it was already chilly. Down to 5C already. Shivering and seeing my breath condense in front of me, I threw on extra layers of clothes. Fortunately I’m not a very big man. Martinez’s clothes fit over mine, and Vogel’s fit over Martinez’s. These shitty clothes were designed to be worn in a temperature-controlled environment. Even with three layers, I was still cold. I climbed in to my bunk and under the covers for more warmth.

Once the temperature got to 1C, I waited another hour, just to make sure the bacteria in the dirt got the memo that it was time to take it slow.

The next problem I ran in to was the regulator. Despite my swaggering confidence, I wasn’t able to outwit it. It really does not want to pull too much O2 out of the air. The lowest I could get it to was 15%. After that, it flatly refused to go lower, and nothing I did mattered. I had all these plans about getting in and reprogramming it. But the safety protocols turned out to be in ROMs.

I can’t blame it. Its whole purpose is to prevent the atmosphere from becoming lethal. Nobody at NASA thought “Hey, let’s allow a fatal lack of oxygen that will make everyone drop dead!”

So I had to use more a more primitive plan.

The regulator uses a different set of vents for air sampling than it does for main air separation. The air that gets freeze-separated comes in through a single large vent on the main unit. But it samples the air from nine small vents that pipe back to the main unit. That way it gets a good average of the Hab, and prevents one localized imbalance from throwing it off.

I taped up eight of the intakes, leaving only one of them active. Then I taped the mouth of a Hefty-sized bag over the neck-hole of a spacesuit (Johanssen’s this time). In the back of the bag, I poked a small hole and taped it over the remaining intake.

Then I inflated the bag with pure O2 from the suit’s tanks. “Holy shit!” the regulator thought, “I better pull O2 out right away!”

Worked great!

I decided I not to wear a space suit after all. The atmospheric pressure was going to be fine. All I needed was oxygen. So I grabbed an O2 canister from the medical bay. That way, I had a hell of a lot more freedom of motion. It even had a rubber band to keep it on my face!

Though I did need a spacesuit to monitor the actual Hab oxygen level (The Hab’s main computer was convinced it was 100% O2). Each spacesuit knew how to monitor its own internal air, of course.

Let’s see… Martinez’s spacesuit was in the rover. Johanssen’s was outwitting the regulator. Lewis’s was serving as a water-tank. I didn’t want to mess with mine (hey, it’s custom fitted!). That left me three spacesuits to work with.

I grabbed Vogel’s suit and activated the internal air sensors while leaving the helmet off. Once the oxygen dropped to 12% I put the breather mask on. I watched it fall further and further. When it reached 1% I cut power to the regulator.

I may not be able to reprogram the regulator, but I can turn the bastard off completely.

The Hab has emergency flashlights in many locations in case of critical power failure. I tore the L.E.D. bulbs out of one and left the two frayed power wires very close together. Now when I turned it on I got a small spark.

Taking a canister of O2 from Vogel’s suit, I attached a strap to both ends and slung it over my shoulder. Then I attached an air line to the tank and crimped it with my thumb. I turned on a very slow trickle of O2; a small enough that it couldn’t overpower the crimp.

Standing on the table with a sparker in one hand and my oxygen line in the other, I reached up and gave it a try.

And holy hell it worked! Blowing the O2 over the sparker, I flicked the switch on the flashlight and a wonderful jet of flame fired out of the tube. The fire alarm went off, of course. But I’d heard it so much lately I barely noticed it any more.