The million dollar question is, where the hell did the oxygen come from? The whole plan was to limit oxygen and keep an explosion from happening. And it was working for quite a while before blowing up.

I think I have my answer. And it comes down to me brain-farting. Remember when I decided not to wear a space suit? That decision almost killed me.

The medical O₂ tank mixes pure oxygen with surrounding air, then feeds it to you through a mask. The mask stays on your face with a little rubber band that goes around the back of your neck. Not an airtight seal.

I know what you’re thinking. The mask leaked oxygen. But no. I was breathing the oxygen. When I was inhaling, I made a nearly airtight seal with the mask by sucking it to my face.

The problem was exhaling. Do you know how much oxygen you absorb out of the air when you take a normal breath? I don’t know either, but it’s not 100 percent. Every time I exhaled, I added more oxygen to the system.

It just didn’t occur to me. But it should have. If your lungs grabbed up all the oxygen, mouth-to-mouth resuscitation wouldn’t work. I’m such a dumb-ass for not thinking of it! And my dumb-assery almost got me killed!

I’m really going to have to be more careful.

It’s a good thing I burned off most of the hydrogen before the explosion. Otherwise that would have been the end. As it is, the explosion wasn’t strong enough to pop the Hab. Though it was strong enough to almost blast my eardrums in.

This all started with me noticing a 60-liter shortfall in water production. Between deliberate burn-off and a bit of unexpected explosion, I’m back on track. The water reclaimer did its job last night and pulled 50 liters of the newly created water out of the air. It’s storing it in Lewis’s spacesuit, which I’ll call “The Cistern” from now on, because it sounds cooler. The other 10 liters of water was directly absorbed by the dry soil.

Lots of physical labor today. I’ve earned a full meal. And to celebrate my first night back in the Hab, I’ll kick back and watch some shitty twentieth-century TV courtesy of Commander Lewis.

The Dukes of Hazzard, eh? Let’s give it a whirl.

LOG ENTRY: SOL 42

I slept in late today. I deserved it. After four nights of awful sleep in the rover, my bunk felt like the softest, most profoundly beautiful feather bed ever made.

Eventually, I dragged my ass out of bed and finished some post-explosion cleanup.

I moved the potato plants back in today. And just in time, too. They’re sprouting. They look healthy and happy. This isn’t chemistry, medicine, bacteriology, nutrition analysis, explosion dynamics, or any other shit I’ve been doing lately. This is botany. I’m sure I can at least grow some plants without screwing up.

Right?

You know what really sucks? I’ve only made 130 liters of water. I have another 470 liters to go. You’d think after almost killing myself twice, I’d be able to stop screwing around with hydrazine. But nope. I’ll be reducing hydrazine and burning hydrogen in the Hab, every ten hours, for another ten days. I’ll do a better job of it from now on. Instead of counting on a clean reaction, I’ll do frequent “hydrogen cleanings” with a small flame. It’ll burn off gradually instead of building up to kill-Mark levels.