by Энди Вейр
I cut each potato in to 4 pieces, making sure each piece had at least 2 eyes. The eyes are where they sprout from. I let them sit for a few hours to harden a bit, then planted them, well spaced apart, in the corner. God speed, little taters. My life depends on you.
Normally, it takes 90 days to yield full sized potatoes. But I can’t wait that long. I’ll need to cut up all the potatoes from this crop to seed the rest of the field.
By setting the Hab temperature to a balmy 25.5C, the plants will grow quicker. Also, the internal lights will provide plenty of “sunlight” and I’ll make sure they get lots of water (once I figure out where to get water). There will be no foul weather, or any parasites to hassle them, or any weeds to compete with for soil or nutrients. With all this going for them, they should yield healthy, sproutable tubers within 40 days.
I figured that was enough being Farmer Mark for one day.
A full meal for dinner. I’d earned it. Plus, I’d burned a ton of calories and I wanted them back.
I rifled through Commander Lewis’s stuff until I found her personal data-stick. Everyone got to bring whatever digital entertainment they wanted, and I was tired of listening to Johanssen’s Beatles Albums for now. Time to see what Lewis had.
Crappy TV shows. That’s what she had. Countless entire runs of TV shows from forever ago.
Well. Beggars can’t be choosers. “Three’s Company” it is.
LOG ENTRY: SOL 29
Over the last few days, I got all the dirt in that I’d need. I prepped the tables and bunks for holding the weight of soil, and even put the dirt in place. There’s still no water to make it viable, but I have some ideas. Really bad ideas, but they’re ideas.
Today’s big accomplishment was setting up the pop-tents.
The problem with the rovers’ pop-tents is they weren’t designed for frequent use.
The idea was you’d throw out a pop-tent, get in, and wait for rescue. The airlock is nothing more than valves and two doors. Equalize the airlock with your side of it, get in. equalize with the other side, get out. This means you lose a lot of air each use. And I’ll need to get in there at least once a day. The total volume of each pop tent is pretty low, so I can’t afford to lose air from it.
I spent hours trying to figure out how to attach a pop-tent airlock to a Hab airlock. I have three airlocks in the Hab. I’d be willing to dedicate two to pop-tents. That would have been awesome.
The frustrating part is pop-tent airlocks can attach to other airlocks! You might have injured people in there, or not enough space suits. You need to be able to get people out without exposing them to the Martian atmosphere.
But the pop-tents were designed for your crewmates to come rescue you in a rover. The airlocks on the Hab are much larger and completely different than the airlocks on the rovers. When you think about it, there’s really no reason to attach a pop-tent to the Hab.
Unless you’re stranded on Mars and everyone thinks you’re dead and you’re in a desperate fight against time and the elements to stay alive. But, you know, other than that edge case there’s no reason.
So I finally decided I’d just take the hit. I’ll be losing some air every time I enter or exit a pop-tent. The good news is each pop-tent has an air feed valve on the outside. Remember, these are emergency shelters. The occupants might need air, and you can provide it from a rover by hooking up an air line. It’s nothing more than a tube that equalizes the rover’s air with the pop-tent’s.
The Hab and the rovers use the same valve and tubing standards, so I was able to attach the pop tents directly to the Hab. That’ll automatically replenish the air I lose with my entries and exits (what we NASA folk call ingress and egress).
NASA was not fucking around with these emergency tents. The moment I pushed the panic button in the rover, there was an ear-popping whoosh as the pop-tent fired out, attached to the rover airlock. It took about two seconds.
I closed the airlock from the rover side and ended up with a nice, isolated pop-tent. Setting up the equalizer hose was trivial (for once I’m using equipment the way it was designed to be used). Then, after a few trips through the airlock (with the air-loss automatically equalized by the Hab) I got the dirt in.
I repeated the process for the other tent. Everything went really easily.
Sigh… water.
In high school, I played a lot of Dungeons and Dragons. (You may not have guessed this Botanist / Mechanical Engineer was a bit of a nerd in high school, but indeed I was). In the game I played a Cleric. One of the magic spells I could cast was “Create Water”. I always thought it was a really stupid spell, and it never came up. Boy what I wouldn’t give to be able to do that in real life right now.
Anyway. That’s a problem for tomorrow.
For tonight, I have to get back to “Three’s Company.” I stopped last night in the middle of the episode where Mr. Roper saw something and took it out of context.
LOG ENTRY: SOL 30
I have an idiotically dangerous plan for getting the water I need. And boy do I mean dangerous. But I don’t have much choice. I’m out of ideas and I’m due for another dirt-doubling in a few days. When I do the final doubling, I’ll be doubling on to all that new soil I’ve brought in. If I don’t wet it first, it’ll just die.
There isn’t a lot of water here on Mars. There’s ice at the poles, but they’re too far away. If I want water I’ll have to make it from scratch. Fortunately, I know the recipe: Take hydrogen. Add oxygen. Burn.
Let’s take them one at a time. I’ll start with oxygen.
I have a fair bit of O2 reserves, but not enough to make 250 liters of water. Two high-pressure tanks at one end of the Hab are my entire supply (plus the air in the Hab of course). They each contain 25 liters of liquid O2. The Hab would only use them in an emergency; it has the Oxygenator to balance the atmosphere. The reason the O2 tanks are here is to feed the spacesuits and rovers.
Anyway, the reserve oxygen would only be enough to make 100L of water (50L of O2 makes 100L of molecules that only have one O each). That would mean no EVAs for me, and no emergency reserves. And it would make less than half the water I need. Out of the question.
But oxygen’s easier to find on Mars than you might think. The atmosphere is 98% CO2. And I happen to have a machine whose sole purpose is liberating oxygen from CO2. Yay Oxygenator!
One problem: The atmosphere is very thin. About 1/90th the pressure on Earth. So it’s hard to collect. Getting air from outside to inside is nearly impossible. The whole purpose of the Hab is to keep that sort of thing from happening. The tiny amount of Martian atmosphere that enters when I use an airlock is laughable.
That’s where the MAV fuel plant comes in.
My crewmates took the MAV away weeks ago. But the bottom half of it stayed behind. NASA is not in the habit of putting unnecessary shit in to orbit. It left the landing gear, ingress ramp, and fuel plant behind. Remember how the MAV made its own fuel with help from the Martian atmosphere? Step one of that is to collect CO2 and store it in a high pressure vessel. Once I get that hooked up to the Hab’s power, it’ll give me half a liter of liquid CO2 per hour, indefinitely. After 5 days it’ll have made 125L of CO2, which will make 125L of O2 after I feed it through the Oxygenator.
That’s enough to make 250L of water. So I have a plan for oxygen.
The hydrogen will be a little trickier.
I considered raiding the hydrogen fuel-cells, but I need those batteries to maintain power at night. If I don’t have that, It’ll get too cold. I could bundle up, but the cold would kill my crops. And each fuel cell only has a small amount of H2 anyway. It’s just not worth sacrificing so much usefulness for so little gain. The one thing I have going for me is that energy is not a problem. I don’t want to give that up.
So I’ll have to go a different route.
I often talk about the MAV. But now I want to talk about the MDV.
During the most terrifying 23 minutes of my life, four of my crewmates and I trie
d not to shit ourselves while Martinez piloted the MDV down to the surface. It was kind of like being in a tumble-dryer.
First, we descended from Hermes, and decelerated our orbital velocity so we could start falling properly. Everything was smooth until we hit the atmosphere. If you think turbulence is rough in a jetliner going 720kph, just imagine what it’s like at 28,000kph.
Several staged sets of chutes deployed automatically to slow our descent, then Martinez manually piloted us to the ground, using the thrusters to slow descent and control our lateral motion. He’d trained for this for years, and he did his job extraordinarily well. He exceeded all plausible expectations of landings, putting us just nine meters from the target. The guy just plain owned that landing.
Thanks, Martinez! You may have saved my life!
Not because of the perfect landing, but because he left so much fuel behind. Hundreds of liters of unused Hydrazine. Each molecule of Hydrazine has four hydrogen atoms in it. So each liter of Hydrazine has enough hydrogen for two liters of water.
I did a little EVA today to check. The MDV has 292L of juice left in the tanks. Enough to make a almost 600L of water! Way more than I need!
There’s just one catch: Liberating hydrogen from Hydrazine is… well… it’s how rockets work. It’s really, really hot. And dangerous. If I do it in an oxygen atmosphere, the heat and newly liberated hydrogen will explode. There’ll be a lot of H2O at the end, but I’ll be too dead to appreciate it.
At its root, Hydrazine is pretty simple. The Germans used it as far back as World War II for rocket-assisted fighter fuel (and occasionally blew themselves up with it).
All you have to do is run it over a catalyst (which I can extract from the MDV engine) and it will turn in to nitrogen and hydrogen. I’ll spare you the chemistry, but the end result is that 5 molecules of Hydrazine becomes 5 molecules of harmless N2 and 10 molecules of lovely H2. During this process, it goes through an intermediate step of being ammonia. Chemistry, being the sloppy bitch it is, ensures there’ll be some ammonia that doesn’t react with the Hydrazine, so it’ll just stay ammonia. You like the smell of ammonia? Well it’ll be prevalent in my increasingly hellish existence.
The chemistry is on my side. The question now is how do I actually make this reaction happen slowly and how do I collect the hydrogen? The answer is: I don’t know.
I suppose I’ll think of something. Or die.
Anyway, much more important: I simply can’t abide the replacement of Chrissie with Cindy. “Three’s Company” may never be the same after this fiasco. Time will tell.
Chapter 4
LOG ENTRY: SOL 32
So I ran in to a bunch of problems with my water plan.
My idea is to make 600L of water (limited by the hydrogen I can get from the Hydrazine). That means I’ll need 300L of liquid O2.
I can create the O2 easily enough. It takes 20 hours for the MAV fuel plant to fill its 10L tank with CO2. The Oxygenator can turn it in to O2, then the Atmospheric Regulator will see the O2 content in the Hab is high, and pull it out of the air, storing it in the main O2 tanks. They’d fill up, so I’d have to transfer O2 over to the rovers’ tanks and even space suit tanks as necessary.
But I can’t create it very quickly. At 1/2L of CO2 per hour, it will take 25 days to make the oxygen I need. That’s longer than I’d like.
Also, there’s the problem of storing the hydrogen. The air tanks of the Hab, the rovers, and all the space suits add up to exactly 374L of storage. To hold all the materials for water, I would need a whopping 900L of storage.
I considered using one of the rovers as a “tank”. It would certainly be big enough, but it just isn’t designed to hold in that much pressure. It’s made to hold (you guessed it) one atmosphere. I need vessels that can hold 50 times that much. I’m sure a rover would burst.
The best way to store the ingredients of water is to make them be water. So what’s what I’ll have to do.
The concept is simple, but the execution will be incredibly dangerous.
Every 20 hours, I’ll have 10L of CO2 thanks to the MAV fuel plant. I’ll vent it in to the Hab via the highly scientific method of detaching the tank from the MAV landing struts, bringing it in to the Hab, then opening the valve until it’s empty.
The Oxygenator will turn it in to oxygen in its own time.
Then, I’ll release Hydrazine, VERY SLOWLY, over the iridium catalyst, to turn it in to N2 and H2. I’ll direct the hydrogen to a small area and burn it.
As you can see, this plan provides many opportunities for me to die in a fiery explosion.
Firstly, Hydrazine is some serious death. If I make any mistakes, there’ll be nothing left but the “Mark Watney Memorial Crater” where the Hab once stood.
Presuming I don’t fuck up with the Hydrazine, there’s still the matter of burning hydrogen. I’m going to be setting a fire. In the Hab. On purpose.
If you asked every engineer at NASA what the worst scenario for the Hab was, they’d all answer “fire.” If you asked them what the result would be, they’d answer “death by fire.”
But if I can pull it off, I’ll be making water continuously, with no need to store hydrogen or oxygen. It’ll be mixed in to the atmosphere as humidity, but the Water Reclaimer will pull it out.
I don’t even have to perfectly match the Hydrazine end of it with the fuel plant CO2 part. There’s plenty of oxygen in the Hab, and plenty more in reserve. I just need to make sure not to make so much water I run myself out of O2.
I hooked up the MAV fuel plant to the Hab’s power supply. Fortunately they both use the same voltage. It’s chugging away, collecting CO2 for me.
Half-ration for dinner. All I accomplished today was thinking up a plan that’ll kill me, and that doesn’t take much energy.
I’m going to finish off the last of “Three’s Company” tonight. Frankly, I like Mr. Furley more than the Ropers.
LOG ENTRY: SOL 33
This may be my last entry.
I’ve known since Sol 6 there was a good chance I’d die here. But I figured it would be when I ran out of food. I didn’t think it would be this early.
I’m about the fire up the Hydrazine.
Our mission was designed knowing that anything might need maintenance, so I have plenty of tools. Even in a space-suit, I was able to pry the access panels off the MDV and get at the six Hydrazine tanks. I set them in the shadow of a rover to keep them from heating up too much. There’s more shade and a cooler temperature near the Hab, but fuck that. If they’re going to blow up, they can blow up a rover, not my house.
Then I pried out the reaction chamber. It took some work and I cracked the damn thing in half, but I got it out. Lucky for me I don’t need a proper fuel reaction. In fact, I really, super-duper don’t want a proper fuel reaction.
I brought all the Hydrazine and reaction chamber in. I briefly considered only having one tank in at a time to reduce risk. But some back-of-the-napkin math told me even one tank was enough to blow the whole Hab up, so why not bring them all in?
The tanks have manual vent valves. I’m not 100% sure what they’re for. Certainly we were never expected to use them. I think they’re there to release pressure during the many quality checks done during construction and before fueling. Whatever the reason, I have valves to work with. All it takes is a wrench.
I liberated a spare water hose from the Water Reclaimer. With some thread torn out of a uniform (Sorry, Johanssen), I attached it to the valve output. Hydrazine is a liquid, so all I have to do is lead it to the reaction chamber (more of a “reaction bowl” now).
Meanwhile, the MAV fuel plant is still working. I’ve already brought in one tank of CO2, vented it, and returned it for refilling.
So there are no more excuses. It’s time to start making water.
If you find the charred remains of the Hab, it means I did something wrong. I’m copying this log over to both rovers so it’s more likely it’ll survive.
Here goes nothin’
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br /> LOG ENTRY: SOL 33 (2)
Well, I didn’t die.
First thing I did was put on the inner lining of my EVA suit. Not the bulky suit itself, just the inner clothing I wear under it, including the gloves and booties. Then I got an oxygen mask from the medical supplies and some lab goggles from Vogel’s chem kit. Almost all of my body was now protected and I would be breathing canned air.
Why? Because Hydrazine is very toxic. If I breathe too much of it I’ll get major lung problems. If I get it on my skin, I’ll have chemical burns for the rest of my life. I wasn’t taking any chances.
I turned the valve until a trickle of Hydrazine came out. I let one drop fall in to the iridium bowl.
It un-dramatically sizzled and disappeared.
But hey, that’s what I wanted. I just freed up hydrogen and nitrogen. Yay!
One thing I have in abundance here is bags. They’re not much different than kitchen trash bags, though I’m sure they cost $50,000 because NASA.
In addition to being our commander, Lewis was also the geologist. She was going to collect rock and soil samples from all over the operational area (10 km radius). Weight limits restricted how much she could actually bring back, so she was going to collect first, then sort out the most interesting 50kg to take home. The bags are to store and tag the samples. Some are smaller than a Ziploc, while others are as big as a Hefty lawn and leaf bag.
Also, I have duct tape. Ordinary duct tape, like you buy at a hardware store. Turns out even NASA can’t improve on duct tape.
I cut up a few Hefty sized bags and taped them together to make a sort of tent. Really it was more of a super-sized bag. I was able to cover the whole table where my Hydrazine mad scientist set-up was. I put a few knickknacks on the table to keep the plastic out of the iridium bowl. Thankfully, the bags are clear, so I can still see what’s going on.
Next, I sacrificed a spacesuit to the cause. I needed an air hose. I have a surplus of space suits, after all. A total of seven; one for each crewmember and one spare. So I don’t mind murdering one of them.
