I started with a large rigid sample container (or “plastic box” to people who don’t work at NASA). I ran a tube through the open top and down the inside wall. Then I coiled it in the bottom to make a spiral. I glued it in place like that and sealed the end. Using my smallest drill bit, I put dozens of little holes in the coil. The idea is for the freezing return air from the regulator to pass through the water as a bunch of little bubbles. The increased surface area will get the heat into the air better.

Then I got a medium flexible sample container (“Ziploc bag”) and tried to seal the RTG in it. But the RTG has an irregular shape, and I couldn’t get all the air out of the bag. I can’t allow any air in there. Instead of heat going to the water, some would get stored in the air, which could superheat and melt the bag.

I tried a bunch of times, but there was always an air pocket I couldn’t get out. I was getting pretty frustrated until I remembered I have an airlock.

Suiting up, I went to Airlock 2 and depressurized to a full vacuum. I plopped the RTG in the bag and closed it. Perfect vacuum seal.

Next came some testing. I put the bagged RTG at the bottom of the container and filled it with water. It holds twenty liters, and the RTG quickly heated it. It was gaining a degree per minute. I let it go until it was a good 40°C. Then I hooked up the regulator’s return air line to my contraption and watched the results.

It worked great! The air bubbled through, just like I’d hoped. Even better, the bubbles agitated the water, which distributed the heat evenly.

I let it run for an hour, and the Hab started to get cold. The RTG’s heat can’t keep up with the total loss from the Hab’s impressive surface area. Not a problem. I’ve already established it’s plenty to keep the rover warm.

I reattached the return air line to the regulator and things got back to normal.

LOG ENTRY: SOL 381

I’ve been thinking about laws on Mars.

Yeah, I know, it’s a stupid thing to think about, but I have a lot of free time.

There’s an international treaty saying no country can lay claim to anything that’s not on Earth. And by another treaty, if you’re not in any country’s territory, maritime law applies.

So Mars is “international waters.”

NASA is an American nonmilitary organization, and it owns the Hab. So while I’m in the Hab, American law applies. As soon as I step outside, I’m in international waters. Then when I get in the rover, I’m back to American law.

Here’s the cool part: I will eventually go to Schiaparelli and commandeer the Ares 4 lander. Nobody explicitly gave me permission to do this, and they can’t until I’m aboard Ares 4 and operating the comm system. After I board Ares 4, before talking to NASA, I will take control of a craft in international waters without permission.