Either it’ll kill me or it won’t. A lot of work went into making sure it doesn’t break. If I can’t trust NASA, who can I trust? (For now I’ll forget that NASA told us to bury it far away.)

I stored it on the roof of the rover for the trip back. That puppy really spews heat.

I have some flexible plastic tubing intended for minor water reclaimer repairs. After bringing the RTG into the Hab, I very carefully glued some tubing around the heat baffles. Using a funnel made from a piece of paper, I ran water through the tubing, letting it drain into a sample container.

Sure enough, the water heated up. That’s not really a surprise, but it’s nice to see thermodynamics being well behaved.

There’s one tricky bit: The atmospheric regulator doesn’t run constantly. The freeze-separation speed is driven by the weather outside. So the returning frigid air doesn’t come as a steady flow. And the RTG generates a constant, predictable heat. It can’t “ramp up” its output.

So I’ll heat water with the RTG to create a heat reservoir, then I’ll make the return air bubble through it. That way I don’t have to worry about when the air comes in. And I won’t have to deal with sudden temperature changes in the rover.

When the Vicodin wore off, my back hurt even more than before. I’m going to need to take it easy. I can’t just pop pills forever. So I’m taking a few days off from heavy labor. To that end, I made a little invention just for me.…

I took Johanssen’s cot and cut out the hammock. Then I draped spare Hab canvas over the frame, making a pit inside the cot, with extra canvas around the edges. Once I weighed down the excess canvas with rocks, I had a water-tight bathtub!

It only took 100 liters to fill the shallow tub.

Then, I stole the pump from the water reclaimer. (I can go quite a while without the water reclaimer operating.) I hooked it up to my RTG water heater and put both the input and output lines into the tub.

Yes, I know this is ridiculous, but I hadn’t had a bath since Earth, and my back hurts. Besides, I’m going to spend 100 sols with the RTG anyway. A few more won’t hurt. That’s my bullshit rationalization and I’m sticking with it.

It took two hours to heat the water to 37°C. Once it did, I shut off the pump and got in. Oh man! All I can say is “Ahhhhhh.”

Why the hell didn’t I think of this before?

LOG ENTRY: SOL 207

I spent the last week recovering from back problems. The pain wasn’t bad, but there aren’t any chiropractors on Mars, so I wasn’t taking chances.

I took hot baths twice a day, lay in my bunk a lot, and watched shitty seventies TV. I’ve already seen Lewis’s entire collection, but I didn’t have much else to do. I was reduced to watching reruns.