The only possible explanation is I haven’t been burning all the released hydrogen.

It’s obvious now, in retrospect. But it never occurred to me that some of the hydrogen just wouldn’t burn. It got past the flame, and went on its merry way. Dammit, Jim, I’m a botanist, not a chemist!

Chemistry is messy, so there's unburned Hydrogen in the air. All around me. Mixed in with the oxygen. Just... hanging out. Waiting for a spark so it can blow the fucking Hab up!

Once I figured this out, and composed myself, I got a Ziploc-sized sample bag and waved it around a bit, then sealed it.

Then, a quick EVA to a rover, where we keep the atmospheric analyzers. Nitrogen: 22%. Oxygen: 9%. Hydrogen: 64%.

I’ve been hiding here in the rover ever since.

It’s Hydrogenville in the Hab.

I’m very lucky it hasn’t blown. Even a small static discharge would have led to “Oh the humanity!”

So, I’m here in Rover 2. I can stay for a day or two, tops, before the CO2 filters from the rover and my spacesuit fill up. I have that long to figure out how to deal with this.

The Hab is now a bomb.

Chapter 5

LOG ENTRY: SOL 38

I’m still cowering in the rover, but I’ve had time to think. And I know how to deal with the hydrogen.

I thought about the Atmospheric Regulator. It pays attention to what’s in the air and balances it. That’s how the excess O2 I've been importing ends up in the tanks. Problem is, it’s just not built to pull hydrogen out of the air.

The regulator uses freeze-separation to sort out the gasses. When it decides there’s too much oxygen, it starts collecting air in a tank and cooling it to 90 kelvin. That makes the oxygen turn to liquid, but leaves the nitrogen (condensation point: 77K) still gaseous. Then it stores the O2.

But I can’t get it to do that for hydrogen, because hydrogen needs to be below 21K to turn liquid. And the regulator just can’t get temperatures that low. Dead end.

Here’s the solution:

Hydrogen is dangerous because it can blow up. But it can only blow up if there’s oxygen around. Hydrogen without oxygen is harmless. And the regulator is all about pulling oxygen out of the air.

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.

LOG ENTRY SOL 38 (2)

Disco. God damn it, Lewis.

LOG ENTRY: SOL 39

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.

LOG ENTRY: SOL 40

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.