The Martian - Page 5/89

In other news, today is Thanksgiving. My family will be gathering in Chicago for the usual feast at my parent's house. My guess is it won't be much fun, what with me having died 11 days ago. Hell, they probably just got done gathering for my funeral.

I wonder if they'll ever find out what really happened.

LOG ENTRY: SOL 22

Wow. Things really came along.

I got all the sand in and ready to go. 2/3 of the base is now dirt. And today I executed my first dirt-doubling. It's been a week, and the former Martian soil was rich and lovely. Two more doublings and I will have covered the whole field. 

All that work was great for my morale. It gave me something to do. But after things settled down a bit, and I had dinner while listening to Johanssen’s Beatles music collection, I got depressed again.

Doing the math, this won’t keep me from starving.

My best bet for making calories is potatoes. They grow prolifically and have a reasonable caloric content (770 calories per kg). I’m pretty sure the ones I have will germinate. Problem is I can’t grow enough of them. In 62 square meters, I could grow maybe 150kg of potatoes in 400 days (the time I have before running out of food). That’s a grand total of 115,500 calories, a sustainable average of 288 calories per day. With my height and weight, if I’m willing to starve a little, I need 1500 calories per day.

Not even close.

So I can’t just live off the land for ever. But I can extend my life. The potatoes will last me 76 days.

Potatoes grow continually, so in those 76 days, I can grow another 22,000 calories of potatoes, which will tide me over for another 15 days. After that, it’s kind of pointless to continue the trend. All told it buys me about 90 days.

So now I’ll start starving to death on Sol 490 instead of Sol 400. It’s progress, but any hope of survival rests on me surviving until Sol 1412, when Ares 4 will land.

There’s about a thousand days of food I don’t have. And I don’t have a plan for how to get it.

Shit.

Chapter 3

LOG ENTRY: SOL 25

Remember those old math questions you had in Algebra class? Where water is entering a container at a certain rate and leaving at a different rate and you need to figure out when it’ll be empty? Well, that concept is critical to the “Mark Watney doesn’t die” project I’m working on.

I need to create calories. And I need enough to last four years. I figure if I don’t get rescued by Ares 4, I’m dead anyway. So that’s my target: four years.

I have plenty of multivitamins; over double what I need. And there’s five times the minimum protein in each food pack, so careful rationing of portions takes care of my protein needs for at least four years. My general nutrition is taken care of. I just need calories.

I need 1500 calories every day. I have 400 days of food to start off with. So how many calories do I need to generate per day along the entire time period to stay alive for 1400 days total (the time till Ares 4 arrives)?

I’ll spare you the math. The answer is a cool 1000. I need to create 1000 calories per day with my farming efforts to survive until Ares 4 gets here. Actually, a little more than that, because it’s sol 25 right now and I haven’t actually planted anything yet.

With my 62 square meters of farmland, I’ll be able to create about 288 calories per day. I need to bring that up to 1000. I need four times my current plan’s production to survive.

I need more surface area for farming, and I need water to hydrate the soil. So let’s take the problems one at a time.

How much farmland can I really make?

There are 92 square meters in the Hab. Let’s say I could make use of all of it.

Also, there are five unused bunks. Let’s say I put soil in on them, too. They’re 2 square meters each, giving me 10 more square meters. So we’re up to 102.

The Hab has three lab tables, each about 2 square meters. I want to keep one for my own use, leaving two for the cause. That’s another four square meters, bringing the total to 106.

I have two Martian rovers. They have pressure seals, allowing the occupants to drive in ease, without spacesuits, as they spent long periods traversing the surface. They’re too cramped to plant crops in, and I want to be able to drive them around anyway. But both rovers have an emergency pop-tent.

There are a lot of problems with using pop-tents as farmland, but they have 10 square meters of floor space each. Presuming I can overcome the problems, they net me another 20 square meters, bringing my farmland up to 126. 

126 square meters of farmable land. That’s something to work with. Not nearly enough water to moisten the soil, but like I said, one thing at a time.

The next thing to consider is how efficient I can be in growing potatoes. I based my crop yield estimates on the potato industry back on Earth. But potato farmers aren’t in a desperate race for survival like I am. Can I get a better yield?

For starters, I can give attention to each individual plant. I can trim them and keep them healthy and not interfering with each other. Also, as their flowering bodies breach the surface, I can replant them deeper, then plant younger plants above them. For normal potato farmers, it’s not worth doing because they’re working with literally millions of potato plants.

Also, this sort of farming annihilates the soil. Any farmer doing it  would turn their land into a dust bowl within 12 years. It’s not sustainable. But who gives a shit? I just need to survive four years.

I estimate I can get 50% higher yield by using these tactics. And with the 126 square meter farmland (just over double the 62 square meters I have) it works out to be over 900 calories per day.

That’s real progress. I’d still be in danger of starvation, but it gets me in the range of survival. I might be able to make it by nearly starving but not quite dying. I could reduce my caloric use by minimizing manual labor. I could set the temperature of the Hab higher than normal, meaning my body expends less energy keeping its temperature. I could cut off an arm and eat it, gaining me valuable calories and reducing my overall caloric need.

No, not really.

So let’s say I could clear up that much farmland. Seems reasonable. Where do I get the water? To go from 62 to 126 square meters of farmland at 10cm deep, I’ll need 6.4 more cubic meters of soil (more shoveling, whee!) and that’ll need over 250 liters of water.

The 50L I have is for me to drink if the Water Reclaimer breaks. So I’m 250L short of my 250L goal.

Bleh. I’m going to bed.

LOG ENTRY: SOL 26

It was a back-breaking yet productive day.