But I need to know the shape of the storm, too.

Dust storms are big. They can be thousands of kilometers across. So when I work my way around it, I’ll need to know which way to go. I’ll want to move perpendicular to the storm’s movement, and in whatever direction has less storm.

So here’s my plan:

Right now, I can go 86 kilometers (because I couldn’t get a full battery yesterday). Tomorrow, I’m going to leave a solar cell here and drive 40 kilometers due south. Then I’ll drop off another solar cell and drive another 40 kilometers due south. That’ll give me three points of reference across 80 kilometers.

The next day, I’ll go back to collect the cells and get the data. By comparing the wattage at the same time of day in those three locations, I’ll learn the shape of the storm. If the storm is thicker to the south, I’ll go north to get around it. If it’s thicker north, I’ll go south.

I’m hoping to go south. Schiaparelli is southeast of me. Going north would add a lot of time to my total trip.

There’s one slight problem with my plan: I don’t have any way to “record” the wattage from an abandoned solar cell. I can easily track and log wattage with the rover computer, but I need something I can drop off and leave behind. I can’t just take readings as I drive along. I need readings at the same time in different places.

So I’m going to spend today working on some mad science. I have to make something that can log wattage. Something I can leave behind with a single solar cell.

Since I’m stuck here for the day anyway, I’ll leave the solar cells out. I may as well get a full battery out of it.

LOG ENTRY: SOL 477

It took all day yesterday and today, but I think I’m ready to measure this storm.

I needed a way to log the time of day and the wattage of each solar cell. One of the cells would be with me, but the other two would be dropped off and left far away. And the solution was the extra EVA suit I brought along.

EVA suits have cameras recording everything they see. There’s one on the right arm (or the left if the astronaut is left-handed) and another above the faceplate. A time stamp is burned into the lower left corner of the image, just like on the shaky home videos Dad used to take.

My electronics kit has several power meters. So I figured, why make my own logging system? I can just film the power meter all day long.

So that’s what I set up. When I packed for this road trip, I made sure to bring all my kits and tools. Just in case I had to repair the rover en route.

First, I harvested the cameras from my spare EVA suit. I had to be careful; I didn’t want to ruin the suit. It’s my only spare. I extracted the cameras and the lines leading to their memory chips.