Chapter 7
I finished making water some time ago. I’m no longer in danger of blowing myself up. The potatoes are growing nicely. Nothing has conspired to kill me in weeks. And seventies TV keeps me disturbingly more entertained than it should. Things are stable here on Mars.
It’s time to start thinking long-term.
Won’t be easy.
It takes eighteen months for the MAV to make its fuel, so it’s the first thing NASA sends along.
Sending it forty-eight months early gives it plenty of extra time in case fuel reactions go slower than expected.
But much more importantly, it means a precision soft landing can be done remotely by a pilot in orbit.
Direct remote operation from Houston isn’t an option; they’re anywhere from four to twenty light-minutes away.
Ares 4’s MAV spent eleven months getting to Mars. It left before us and got here around the same time we did. As expected, Martinez landed it beautifully. It was one of the last things we did before piling into our MDV and heading to the surface. Ahh, the good old days, when I had a crew with me.
I’m lucky. Thirty-two hundred km isn’t that bad. It could have been up to 10,000 km away. And because I’m on the flattest part of Mars, the first 650 kilometers is nice, smooth terrain (Yay Acidalia Planitia!) but the rest of it is nasty, rugged, crater-pocked hell.
Obviously, I’ll have to use a rover. And guess what? They weren’t designed for massive overland journeys.
This is going to be a research effort, with a bunch of experimentation. I’ll have to become my own little NASA, figuring out how to explore far from the Hab. The good news is I have lots of time to figure it out. Almost four years.
Some stuff is obvious. I’ll need to use a rover. It’ll take a long time, so I’ll need to bring supplies. I’ll need to recharge en route, and rovers don’t have solar cells, so I’ll need to steal some from the Hab’s solar farm. During the trip I’ll need to breathe, eat, and drink.
Lucky for me, the tech specs for everything are right here in the computer.
I’ll need to trick out a rover. Basically it’ll have to be a mobile Hab. I’ll pick Rover 2 as my target. We have a certain bond, after I spent two days in it during the Great Hydrogen Scare of Sol 37.
There’s too much shit to think about all at once. So for now, I’ll just think about power.
Our mission had a 10-kilometer operational radius. Knowing we wouldn’t take straight-line paths, NASA designed the rovers to go 35 kilometers on a full charge. That presumes flat, reasonable terrain. Each rover has a 9000-watt-hour battery.
Step one is to loot Rover 1’s battery and install it in Rover 2. Ta-daa! I just doubled my full-charge range.
There’s just one complication. Heating.
Part of the battery power goes to heating the rover.
Mars is really cold. Normally, we were expected to do all EVAs in under five hours.
But I’ll be living in it twenty-four and a half hours a day.
According to the specs, the heating equipment soaks up 400 watts.
Keeping it on would eat up 9800 watt hours per day. Over half my power supply, every day!
But I do have a free source of heat: me. A couple million years of evolution gave me “warm-blooded” technology. I can just turn off the heater and wear layers. The rover has good insulation, too. It’ll have to be enough; I need every bit of power.
According to my boring math, moving the rover eats 200 watt hours of juice to go 1 kilometer, so using the full 18,000 watt hours for motion (minus a negligible amount for computer, life support, etc.) gets me 90 kilometers of travel. Now we’re talkin’.
I’ll never actually get 90 kilometers on a single charge. I’ll have hills to deal with, and rough terrain, sand, etc. But it’s a good ballpark. It tells me that it would take at least 35 days of travel to get to Ares 4. It’ll probably be more like 50. But that’s plausible, at least.
At the rover’s blazing 25 kph top speed, it’ll take me three and a half hours before I run the battery down.
I can drive in twilight, and save the sunny part of the day for charging.
This time of year I get about thirteen hours of light.
How many solar cells will I have to pilfer from the Hab’s farm?
Thanks to the fine taxpayers of America, I have over 100 square meters of the most expensive solar paneling ever made.
It has an astounding 10.2 percent efficiency, which is good because Mars doesn’t get as much sunlight as Earth.
Only 500 to 700 watts per square meter (compared to the 1400 Earth gets).
Long story short: I need to bring twenty-eight square meters of solar cell. That’s fourteen panels.
I can put two stacks of seven on the roof. They’ll stick out over the edges, but as long as they’re secure, I’m happy. Every day, after driving, I’ll spread them out then…wait all day. Man it’ll be dull.
Well it’s a start. Tomorrow’s mission: transfer Rover 1’s battery to Rover 2.
LOG ENTRY: SOL 64
Sometimes things are easy, and sometimes they’re not. Getting the battery out of Rover 1 was easy. I removed two clamps on the undercarriage and it dropped right out. The cabling was easy to detach, too, just a couple of complicated plugs.
Attaching it to Rover 2, however, is another story. There’s nowhere to put it!
The thing is huge . I was barely able to drag it. And that’s in Mars gravity.
It’s just too big. There’s no room in the undercarriage for a second one. There’s no room on the roof, either. That’s where the solar cells will go. There’s no room inside the cabin, and it wouldn’t fit through the airlock anyway.
But fear not, I found a solution.
For emergencies completely unrelated to this one, NASA provided six square meters of extra Hab canvas and some really impressive resin. The same kind of resin, in fact, that saved my life on Sol 6 (the patch kit I used on the hole in my suit).
In the event of a Hab breach, everyone would run to the airlocks. Procedure was to let the Hab pop rather than die trying to prevent it. Then, we’d suit up and assess the damage. Once we found the breach, we’d seal it with the spare canvas and resin. Then reinflate and we’re good as new.
The six square meters of spare canvas was a convenient one by six meters. I cut 10-centimeter-wide strips, then used them to make a sort of harness.
I used the resin and straps to make two 10-meter circumference loops. Then I put a big patch of canvas on each end. I now had poor man’s saddlebags for my rover.
This is getting more and more Wagon Train every day.
The resin sets almost instantly. But it gets stronger if you wait an hour. So I did. Then I suited up and headed out to the rover.
I dragged the battery to the side of the rover and looped one end of the harness around it. Then I threw the other end over the roof. On the other side, I filled it with rocks. When the two weights were roughly equal, I was able to pull the rocks down and bring the battery up.
Yay!
I unplugged Rover 2’s battery and plugged in Rover 1’s. Then I went through the airlock to the rover and checked all systems. Everything was a-okay.
I drove the rover around a bit to make sure the harness was secure. I found a few largish rocks to drive over, just to shake things up. The harness held. Hell yeah.
For a short time, I wondered how to splice the second battery’s leads into the main power supply. My conclusion was “Fuck it.”
There’s no need to have a continuous power supply. When Battery 1 runs out, I can get out, unplug Battery 1, and plug in Battery 2. Why not? It’s a ten-minute EVA, once per day. I’d have to swap batteries again when I’m recharging them, but again, so what?
I spent the rest of the day sweeping off the solar cell farm. Soon, I shall be looting it.
LOG ENTRY: SOL 65
The solar cells were a lot easier to manage than the battery.
They’re thin, light, and just lying around on theground. And I had one additional bonus: I was the one who set them up in the first place.
Well, okay. It wasn’t just me. Vogel and I worked together on it.
And boy did we drill on it. We spent almost an entire week drilling on the solar array alone.
Then we drilled more whenever they figured we had spare time.
The array was mission-critical. If we broke the cells or rendered them useless, the Hab wouldn’t be able to make power, and the mission would end.
You might wonder what the rest of the crew was doing while we assembled the array. They were setting up the Hab. Remember, everything in my glorious kingdom came here in boxes. We had to set it up on Sols 1 and 2.
Each solar cell is on a lightweight lattice that holds it at a 14-degree angle.
I’ll admit I don’t know why it’s a 14-degree angle.
Something about maximizing solar energy.
Anyway, removing the cells was simple, and the Hab can spare them.
With the reduced load of only supporting one human instead of six, a 14 percent energy production loss is irrelevant.
Then it was time to stack them on the rover.
I considered removing the rock sample container. It’s nothing more than a large canvas bag attached to the roof. Way too small to hold the solar cells. But after some thought I left it there, figuring it would provide a good cushion.
The cells stacked well (they were made to, for transport to Mars), and the two stacks sat nicely on the roof. They hung over the left and right edges, but I won’t be going through any tunnels, so I don’t care.
With some more abuse of the emergency Hab material, I made straps and tied the cells down. The rover has external handles near the front and back. They’re there to help us load rocks on the roof. They made perfect anchor points for the straps.
I stood back and admired my work. Hey, I earned it. It wasn’t even noon and I was done.