At the very least, I need to travel faster than the storm. If I can go faster, I can maneuver around it without being enveloped. I need to find out how fast it’s moving.
I can do that by sitting here for a sol. I can compare tomorrow’s wattage to today’s. All I have to do is make sure to compare the same times of day. Then I’d know how fast the storm is moving, at least in terms of percent power loss.
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 86km (because I couldn’t get a full battery yesterday). I’m going to leave a solar cell here and drive 40km due south. Then I’ll drop off another solar cell and drive another 40km due south. I’ll have three points of reference across 80km.
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.
It took all day yesterday and today, but I think I’m ready to measure this storm.
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.
I made the bedroom in to a lab. I stacked my supply containers to form a rudimentary table, and used a sample box as a stool.
I needed a way to track the time of day and the wattage of the solar cell. The tricky part is logging it. And the solution is the extra EVA suit I brought along.
The cool thing about EVA suits is they have cameras recording everything they see. There’s a camera on the right arm (or the left if the astronaut is left handed), and one above the faceplate. A time-stamp is burned in to the lower left corner of the image, just like the shaky home videos Dad used to take.
My electronics kit has several power meters. So I figure: why make my own logging system? I can just film the power meter all day long.
So that’s what I set up.
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 had to get the cameras and the lines leading to their memory chips.
I put a power meter in to 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 it get power once I abandon it on the surface? Well, it turns out it’s going to be attached to a 2 square meter solar cell. That’ll be plenty. 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 is heat, or the lack thereof. As soon as I take this thing out of the rover, it’ll start cooling down mighty fast. Once it gets too cold, the electronics will stop working entirely.
So I needed a heat source. And my electronics kit provided the answer. Resistors. Lots and lots of them. The camera and power meter only need a tiny fraction of what a solar cell can make. So I’m dumping the rest of the energy through resistors.
Resistors heat up. It’s what they do. There’s my heat source.
I made and tested two “power loggers”, and confirmed 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%. Compared to yesterday’s 97%. So right now, the storm is moving at 4.5% per sol. If I were to stay here another 16 sols, it would get dark enough to kill me.
Just as well I’m not going to stay here.
Everything went as planned today. No hiccups. I can’t tell if I’m driving deeper in to 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 40km travel due south, I had a quick EVA to set up another. Now I’ve gone the full 80km, 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 in to 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.
I bring it up because I dined on a meal pack today. I had saved 5 packs for special occasions. I ate the first of them 29 sols ago when I left for Schiaparelli. I totally forgot to eat the second when I reached the half-way point 9 sols ago. So I’m enjoying my belated half-way feast.
It’s probably more accurate to eat it today anyway. Who knows how long it’ll take me to go around this storm. And if I end up stuck in the storm and doomed to die, I’m totally eating the other earmarked meals.
Have you ever taken the wrong freeway entrance? You need to drive to the next exit to turn around, but you hate every inch of travel because you’re going away from your goal.
I felt like that all day. I’m now back where I started yesterday morning. Yuk.
Along the way, I picked up the power-logger I’d left behind at the half-way point. Just now I brought in the one I’d left here yesterday.
Both loggers worked they way I’d hoped. I downloaded each of their video recordings to a laptop and advanced them to noon. Finally I had solar efficiency readings from three locations along an 80km line, all from the same time of day.
As of noon yesterday, the northern-most logger showed 12.3% efficiency loss, the middle one was a 9.5% loss, and the rover recorded a 6.4% loss at its southernmost location. It paints a pretty clear picture: the storm front runs northwest to southeast. And I already worked out it’s traveling west.
The best way to avoid it is to go south.
Finally, some good news! South is what I wanted. I won’t lose much time.
Sigh… I have to drive the same god damned path a third time tomorrow.
I think I’m getting ahead of the storm.
Having traveled along Mars Highway 1 all day, I’m back at my campsite from yesterday. Tomorrow, I’ll finally make real headway again. I was done driving and had the camp set up by noon. The efficiency loss here is 15.6%. Compared to the 17% loss at yesterday’s camp, this means I can outrun the storm as long as I keep heading south.