The hull sat on Panel A, one of four sides of the tetrahedron which brought Pathfinder to Mars. The other three sides are still in Ares Vallis where I left them.
Between Panel A and the workbench were the Mylar balloons Pathfinder had used to tumble-land. I had shredded many of them to transport it, but a lot of material remained—enough to reach around Panel A and be in contact with the hull. I should mention that Mylar is conductive.
At 13:30, I leaned the drill against the workbench. The drill’s cowling was off to make room for the power line. The workbench is metal. If the drill leaned against the workbench just right, it could make a metal-to-metal connection.
And that’s exactly what had happened.
Power traveled from the drill line’s positive lead, through the workbench, through the Mylar, through Pathfinder’s hull, through a bunch of extremely sensitive and irreplaceable electronics, and out the negative lead of Pathfinder’s power line.
Pathfinder operates on 50 milliamps. It got 9000 milliamps, which plowed through the delicate electronics, frying everything along the way. The breakers tripped, but it was too late.
Pathfinder’s dead. I’ve lost the ability to contact Earth.
I’m on my own.
CHAPTER 18
Sigh…
Just once I’d like something to go as planned, ya know?
Mars keeps trying to kill me.
Well… Mars didn’t electrocute Pathfinder. So I’ll amend that:
Mars and my stupidity keep trying to kill me.
Okay, enough self-pity. I’m not doomed. Things will just be harder than planned. I have all I need to survive. And Hermes is still on the way.
I spelled out a Morse code message using rocks. “PF FRIED WITH 9 AMPS. DEAD FOREVER. PLAN UNCHANGED. WILL GET TO MAV.”
If I can get to the Ares 4 MAV, I’ll be set. But having lost contact with NASA, I have to design my own Great Martian Winnebago to get there.
For the time being, I’ve stopped all work on it. I don’t want to continue without a plan. I’m sure NASA had all kinds of ideas, but now I have to come up with one on my own.
As I mentioned, the Big Three (atmospheric regulator, oxygenator, and water reclaimer) are critical components. I worked around them for my trip to Pathfinder. I used CO2 filters to regulate the atmosphere, and brought enough oxygen and water for the whole trip. That won’t work this time. I need the Big Three.
Problem is, they soak up a lot of power, and they have to run all day long. The rover batteries have 18 kilowatt-hours of juice. The oxygenator alone uses 44.1 kilowatt-hours per sol. See my problem?
You know what? “Kilowatt-hours per sol” is a pain in the ass to say. I’m gonna invent a new scientific unit name. One kilowatt-hour per sol is… it can be anything… um… I suck at this… I’ll call it a “pirate-ninja.”
All told, the Big Three need 69.2 pirate-ninjas, most of that going to the oxygenator and the atmospheric regulator. (The water reclaimer only needs 3.6 of that.)
There’ll be cutbacks.
The easiest cutback is the water reclaimer. I have 620 liters of water (I had a lot more before the Hab blew up). I need only three liters of water per sol, so my supply will last 206 sols. There’s only 100 sols after I leave and before I’m picked up (or die in the attempt).
Conclusion: I don’t need the water reclaimer at all. I’ll drink as needed and dump my waste outdoors. Yeah, that’s right, Mars, I’m gonna piss and shit on you. That’s what you get for trying to kill me all the time.
There. I saved myself 3.6 pirate-ninjas.
I’ve had a breakthrough with the oxygenator!
I spent most of the day looking at the specs. It heats CO2 to 900°C, then passes it over a zirconia electrolysis cell to yank the carbon atoms off. Heating the gas is what takes most of the energy. Why is that important? Because I’m just one guy and the oxygenator was made for six. One-sixth the quantity of CO2 means one-sixth the energy to heat it.
The spec says it draws 44.1 pirate-ninjas, but all this time it’s only been using 7.35 because of the reduced load. Now we’re getting somewhere!
Then there’s the matter of the atmospheric regulator. The regulator samples the air, figures out what’s wrong with it, and corrects the problem. Too much CO2? Take it out. Not enough O2? Add some. Without it, the oxygenator is worthless. The CO2 needs to be separated in order to be processed.
The regulator analyzes the air with spectroscopy, then separates the gasses by supercooling them. Different elements turn to liquid at different temperatures. On Earth, supercooling this much air would take ridiculous amounts of energy. But (as I’m acutely aware) this isn’t Earth.
Here on Mars, supercooling is done by pumping air to a component outside the Hab. The air quickly cools to the outdoor temperature, which ranges from −150°C to 0°C. When it’s warm, additional refrigeration is used, but cold days can turn air to liquid for free. The real energy cost comes from heating it back up. If it came back to the Hab unheated, I’d freeze to death.
“But wait!” You’re thinking, “Mars’s atmosphere isn’t liquid. Why does the Hab’s air condense?”
The Hab’s atmosphere is over 100 times as dense, so it turns to liquid at much higher temperatures. The regulator gets the best of both worlds. Literally. Side note: Mars’s atmosphere does condense at the poles. In fact, it solidifies into dry ice.
Problem: The regulator takes 21.5 pirate-ninjas. Even adding some of the Hab’s power cells would barely power the regulator for a sol, let alone give me enough juice to drive.
More thinking is required.
I’ve got it. I know how to power the oxygenator and atmospheric regulator.
The problem with small pressure vessels is CO2 toxicity. You can have all the oxygen in the world, but once the CO2 gets above 1 percent, you’ll start to get drowsy. At 2 percent, it’s like being drunk. At 5 percent, it’s hard to stay conscious. Eight percent will eventually kill you. Staying alive isn’t about oxygen, it’s about getting rid of CO2.
That means I need the regulator. But I don’t need the oxygenator all the time. I just need to get CO2 out of the air and back-fill with oxygen. I have 50 liters of liquid oxygen in two 25-liter tanks here in the Hab. That’s 50,000 liters in gaseous form, enough to last 85 days. Not enough to see me through to rescue, but a hell of a lot.
The regulator can separate the CO2 and store it in a tank, and it can add oxygen to my air from my oxygen tanks as needed. When I run low on oxygen, I can camp out for a day and use all my power to run the oxygenator on the stored CO2. That way, the oxygenator’s power consumption doesn’t eat up my driving juice.
So I’ll run the regulator all the time, but only run the oxygenator on days I dedicate to using it.
Now, on to the next problem. After the regulator freezes the CO2 out, the oxygen and nitrogen are still gasses, but they’re −75°C. If the regulator fed that back to my air without reheating it, I’d be a Popsicle within hours. Most of the regulator’s power goes to heating the return air so that doesn’t happen.