The Martian (34 page)

1) The only explanation for asymmetrical visibility is a dust storm.

2) Dust storms reduce the effectiveness of solar cells.

3) My solar cells have been slowly losing effectiveness for several sols.

From this, I concluded the following:

1) I've been in a dust storm for several sols.

2) Shit.

Not only am I in a dust storm, but it gets thicker as I approach Schiaparelli. A few hours ago, I was worried because I had to go around Marth Crater. Now I'm going to have to go around something a fuckload bigger.

And I have to hustle. Dust storms move. Sitting still means I'll likely get overwhelmed. But which way do I go? It's no longer an issue of trying to be efficient. If I go the wrong way this time, I'll eat dust and die.

I don't have satellite imagery. I have no way of knowing the size or shape of the storm, or its heading. Man, I'd give anything for a 5-minute conversation with NASA. Now that I think of it, NASA must be shitting bricks watching this play out.

I'm on the clock. I have to figure out
how
to figure out what I need to know about the storm. And I have to do it now.

And right this second nothing comes to mind.

Mindy trudged to her computer. Today's shift began at 2:10pm. Her schedule matched Watney's every day. She slept when he slept. Watney simply slept at night on Mars, while Mindy had to drift 40 minutes forward every day, taping aluminum foil to her windows to get any sleep at all.

She brought up the most recent satellite images. She cocked an eyebrow. He had not broken camp yet. Usually he drove in the early morning, as soon as it was light enough to navigate. Then he capitalized on the midday sun to maximize recharging.

But today, he had not moved, and it was well past morning.

She checked around the rovers and bedroom for a message. She found it in the usual place (north of the campsite). Reading the Morse code, her eyes widened.

“DUST STORM. MAKING PLAN.”

Fumbling with her cell phone, she dialed Venkat's personal number.

LOG ENTRY: SOL 476

I think I can work this out.

I'm on the very edge of a storm. I don't know its size or heading. But it's moving, and that's something I can take advantage of. I don't have to wander around exploring it. It'll come to me.

The storm is just dust in the air; it's not dangerous to the rovers. I can think of it as “Percent power loss.” I checked yesterdays power generation and it was 97% of optimal. So right now, it's a 3% storm.

I need to make progress and I need to regenerate oxygen. Those are my two main goals. I use 20% of my overall power to reclaim oxygen (when I stop for Air Days). If I end up in an 81% part of the storm, I'll be in real trouble. I'll run out of oxygen even if I dedicate all available power to it. That's the fatal scenario. But really, it's fatal much earlier than that. I need power to move or I'll be stranded until the storm passes or dissipates. That could be months.  

The more power I generate, the more I'll have for movement. With clear skies, I dedicate 80% of my total power toward movement. I get 90km per sol this way. So Right now, at 3% loss, I'm getting 3.3km less than I should.

It's ok to lose some driving distance per sol. I have plenty of time, but I can't let myself get too deep in the storm or I'll never be able to get out.

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.

LOG ENTRY: SOL 477

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.

LOG ENTRY: SOL 478

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.

LOG ENTRY: SOL 479

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.

LOG ENTRY: SOL 480

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.

Hopefully.

The storm is
probably
circular. They usually are. But I could just be driving in to an alcove. If that's the case, I'm just fucking dead, ok? There's only so much I can do.

I'll know soon enough. If the storm is circular, I should get better and better efficiency every day until I'm back to 100%. One I reach 100% that means I'm completely south of the storm and I can start going east again. We'll see.

If there were no storm, I'd be going directly southwest toward my goal. As it is, going only south, I'm not nearly as fast. I'm traveling 90km per day as usual, but I only get 37km closer to Schiaparelli because Pythagoras is a dick. I don't know when I'll finally clear the storm and be able to beeline to Schiaparelli again. But one thing's for sure: My plan to arrive on Sol 495 is boned.

Sol 549. That's when they come for me. If I miss it, I'll spend the rest of my very short life here. And I still have the MAV to modify before then, too.

Sheesh.

LOG ENTRY: SOL 482

Air day. A time for relaxation and speculation.

For relaxation, I read 100 pages of Agatha Christie's
Evil Under the Sun
courtesy of Johanssen's digital book collection. I think Linda
Marshall is the murderer
.
 

As for speculation, I speculated on when the hell I'll get past this fucking storm.

I'm still going due south every day; and still dealing with efficiency loss (though I'm keeping ahead of it). Every day of this crap I'm only getting 37km closer to the MAV instead of 90. Pissing me off.

I considered skipping the Air Day. I could go another couple of days before I ran out of oxygen, and getting away from the storm is pretty important. But I decided against it. I'm ahead of the storm enough that I can afford one day of no movement. And I don't know if a couple more days would help. Who knows how far the storm goes south?

Well, NASA probably knows. And the news stations back on Earth are probably showing it. And there's probably a website like www.watch-mark-watney-die.com. So there's like a hundred million people or so who know exactly how far south it goes.

But I'm not one of them.

LOG ENTRY: SOL 484

Finally!

I am FINALLY past the god damned storm. Today's power regen was 100%. No more dust in the air. With the storm moving perpendicular to my direction of travel, it means I'm south of the southernmost point of the cloud (presuming it's a circular storm. If it's not then fuck.)