I put a power meter into a small sample container, then glued a camera to the underside of the lid. When I sealed up the container, the camera was properly recording the readout of the power meter.

For testing, I used rover power. How will my logger get power once I abandon it on the surface? It’ll be attached to a two-square-meter solar cell! That’ll provide plenty of power. And I put a small rechargeable battery in the container to tide it over during nighttime (again, harvested from the spare EVA suit).

The next problem was heat, or the lack thereof. As soon as I take this thing out of the rover, it’ll start cooling down mighty fast. If it gets too cold, the electronics will stop working.

So I needed a heat source. And my electronics kit provided the answer: resistors. Lots and lots of them. Resistors heat up. It’s what they do. The camera and the power meter only need a tiny fraction of what a solar cell can make. So the rest of the energy goes through resistors.

I made and tested two “power loggers” and confirmed that the images were being properly recorded.

Then I had an EVA. I detached two of my solar cells and hooked them up to the power loggers. I let them log happily for an hour, then brought them back in to check the results. They worked great.

It’s getting toward nightfall now. Tomorrow morning, I’ll leave one power logger behind and head south.

While I was working, I left the oxygenator going (why not?). So I’m all stocked up on O₂ and good to go.

The solar cell efficiency for today was 92.5 percent. Compared to yesterday’s 97 percent. This proves the storm is moving east to west, because the denser part of the storm was to the east yesterday.

So right now, the sunlight in this area is dropping by 4.5 percent per sol. If I were to stay here another sixteen sols, it would get dark enough to kill me.

Just as well I’m not going to stay here.

LOG ENTRY: SOL 478

Everything went as planned today. No hiccups. I can’t tell if I’m driving deeper into the storm or out of it. It’s hard to tell if the ambient light is less or more than it was yesterday. The human brain works hard to abstract that out.

I left a power logger behind when I started out. Then, after 40 kilometers’ travel due south, I had a quick EVA to set up another. Now I’ve gone the full 80 kilometers, set up my solar cells for charging, and I’m logging the wattage.

Tomorrow, I’ll have to reverse course and pick up the power loggers. It may be dangerous; I’ll be driving right back into a known storm area. But the risk is worth the gain.

Also, have I mentioned I’m sick of potatoes? Because, by God, I am sick of potatoes. If I ever return to Earth, I’m going to buy a nice little home in Western Australia. Because Western Australia is on the opposite side of Earth from Idaho.