LOG ENTRY: SOL 505
I finally made it! I'm at the MAV!
Well, right this second, I'm back in the rover. I did go in to the MAV to do a systems check and boot-up. I had to keep my EVA suit on the whole time because there's no life support in there just yet.
It's going through a self check right now, and I'm feeding it oxygen and nitrogen with hoses from the rover. This is all part of the MAV's design. It doesn't bring air along. Why would it? That's a needless weight when you'll have a Hab full of air right next door.
I'm guessing folks at NASA are popping champagne right now and sending me lots of messages. I'll read them in a bit. First things first: Get the MAV some life support. Then I'll be able to work comfortably inside.
And then I'll have a boring conversation with NASA. The content may be interesting, but the 14-minute transmission time between here and Earth will be a bit dull.
[13:07]HOUSTON: Congratulations from all of us here at Mission Control! Well done! What's your status?
[13:21]MAV: Thanks! No health or physical problems. The rover and trailer are getting pretty worn out, but still functional. Oxygenator and Regulator both working fine. I didn't bring the Water Reclaimer. Just brought the water. Plenty of potatoes left. I'm good to last till 549.
[13:36]HOUSTON: Glad to hear it. Hermes is still on track for a Sol 549 flyby. As you know, the MAV will need to lose some weight to make the intercept. We're going to get you those procedures within the day. How much water do you have? What did you do with urine?
[13:50]MAV: I have 550L of remaining water. I've been dumping urine outside along the way.
[14:05]HOUSTON: Preserve all water. Don't do any more urine dumps. Store it somewhere. Turn the rover's radio on and leave it on. We can contact it through MAV.
“So is it ready?” Venkat asked.
“Yes, it's ready.” Bruce said. “But you're not going to like it.”
“Go on.”
“Bear in mind,” Bruce said, producing a booklet from his briefcase, “This is the end result of thousands of hours of work, testing, and lateral thinking by all the best guys at JPL.”
“I'm sure it was hard to trim down a ship that's already designed to be as light as possible,” Venkat said.
Bruce slid the booklet across the desk to Venkat. “The problem is the intercept velocity. The MAV is designed to get to Low Mars Orbit, which is 4.1kps. But the Hermes flyby will be 5.8kps.”
Venkat flipped through the pages. “Care to summarize?”
“Firstly, we're going to add fuel. The MAV makes its own fuel from the Martian atmosphere, but it's limited by how much Hydrogen it has. It brought enough to make 19,397kg of fuel, as it was designed to do. If we can give it more hydrogen, it can make more.”
“How much more?”
“For every kilogram of hydrogen, it can make 13 kilograms of fuel. Watney has 550 liters of water. We'll have him electrolyze it to get 60kg of Hydrogen.” Bruce reached over the desk and flipped a few pages, pointing to a diagram. “The fuel plant can make 780kg of fuel from that.”
“If he electrolyzes his water what'll he drink?”
“He can electrolyze urine, so we only need to set a few liters aside for the last couple of days.”
“I see. And what does 780kg of fuel buy us?” Venkat asked.
“It buys us 300kg of payload. It's all about fuel versus payload. The MAV's launch weight is over 12,600kg. We need to get that down to 7,300kg. That's accounting for the bonus fuel. So the rest of this booklet is how to remove over five thousand kilograms from the ship.”
Venkat leaned back. “Walk me through it.”
Bruce pulled another copy of the booklet from his briefcase. “There were some gimmies right off the bat. The design presumes 500kg of Martian soil and rock samples. Obviously we won't do that. Also, there's just one passenger instead of six. That saves 500kg when you consider their weight plus their suits and gear. And we can lose the other 5 acceleration chairs. And of course, we'll remove all nonessential gear. The med kit, tool kit, internal harnessing, straps, and anything else that isn't nailed down. And some stuff that is.
“Next up,” he continued, “We're ditching all life support. The tanks, pumps, heaters, air lines, CO2 absorption system, even the insulation on the inner side of the hull. We don't need it. We'll have Watney wear his EVA suit for the whole trip.”
“Won't that make it awkward for him to use the controls?” Venkat asked.
“He won't use any controls,” Bruce said. “Major Martinez will pilot the MAV remotely from Hermes. It's already designed for remote piloting. It was remotely landed, after all.”
“What if something goes wrong?” Venkat asked.
“Martinez is the best trained pilot,” Bruce said. “If there is an emergency, he's the guy you want controlling the ship.”
“Hmm,” Venkat said cautiously. “We've never had a manned ship controlled remotely before. But ok. Go on.”
“Since Watney won't be flying the ship,” Bruce continued, “he won't need any of those controls. We'll ditch the control panels and all the power and data lines that lead to them.”
“Wow,” Venkat said. “We're really gutting this thing.”
“I'm just getting started,” Bruce said. “The power needs will be dramatically reduced now that life support is gone, so we'll dump three of the five batteries and the auxiliary power system. The Orbital Maneuvering System has 3 redundant thrusters. We'll get rid of those. Also, the secondary and tertiary comm systems can go.”
“Wait, what?” Venkat said, shocked. “You're going to have a remote controlled ascent with no backup comm systems?”
“No point,” Bruce said. “If the comm system goes out during ascent, the time it takes to reacquire will be too long to do any good. The backups don't help us.”
“This is getting really risky, Bruce.”
Bruce sighed. “I know, Venkat. There's just no other way. And I'm not even to the nasty stuff yet.”
Venkat rubbed his forehead. “By all means, tell me the nasty stuff.”
“We'll remove the nose airlock, the windows, and Hull Panel 19.”
Venkat blinked. “You're taking the front of the ship off?”
“Sure,” Bruce said. “The nose airlock alone is 400kg. The windows are pretty damn heavy, too. And they're connected by Hull Panel 19 so may as well take that, too.”
“So he's going to launch with a big hole in the front of the ship?”
“We'll have him cover it with Hab canvas.”
“Hab canvas? For a launch to orbit!?”
Bruce shrugged. “The hull's mostly there to keep the air in. Mars's atmosphere is so thin you don't need a lot of streamlining. By the time the ship's going fast enough for air resistance to matter, it'll be high enough that there's practically no air. We've run all the simulations. Should be good.”
“You're sending him to space under a tarp.”
“Pretty much, yeah.”
“Like a hastily loaded pick up truck.”
“Yeah. Can I go on?”
“Sure, can't wait.”
“We'll also have him remove the back panel of the pressure vessel. It's the only other panel he can remove with the tools on-hand. Also, we're getting rid of the auxiliary fuel pump. Sad to see it go, but it weighs too much for its usefulness. And we're nixing a Stage One engine.”
“An engine?”
“Yeah. The Stage One booster works fine if one engine goes out. It'll save us a huge amount of weight. Only during the Stage One ascent, but still. Pretty good fuel savings.”
Bruce fell silent.
“That it?” Venkat asked.
“Yeah.”
Venkat sighed. “You've removed most of the safety backups. What's this do to the estimated odds of failure?”
“It's about 4%.”
“Jesus Christ.” Venkat said. “Normally we'd never even consider something that risky.”
“It's all we've got, Venk,” Bruce said. “We've tested it all out and run simulations galore. We should be ok if everything works the way its supposed to.”
“Yeah. Great.” Venkat said.
[08:41]MAV: You fucking kidding me?
[09:55]HOUSTON: Admittedly, they are very invasive modifications, but they have to be done. The procedure doc we sent has instructions for each of these steps with tools you have on hand. Also, you'll need to start electrolyzing water to get the hydrogen for the fuel plant. We'll send you procedures for that shortly.
[09:09]MAV: You're sending me into space in a convertible.
[09:24]HOUSTON: There will be Hab canvas covering the holes. It will provide enough aerodynamics in Mars's atmosphere.
[09:38]MAV: So it's a ragtop. Much better.
LOG ENTRY: SOL 506
On the way here, in my copious free time, I designed a “workshop.” I figured I'd need space to work on stuff without having to wear an EVA suit. I devised a brilliant plan whereby the current bedroom would become the new home of the Regulator and Oxygenator, and the now-empty trailer would become my workshop.
It's a stupid idea and I'm not doing it.
All I need is a pressurized area that I can work in. I somehow convinced myself that the bedroom wasn't an option because it's a hassle to get stuff into it. But it won't be that bad.
It attaches to the rover airlock, so the only way to get stuff in is annoying. Bring the stuff into the rover, attach the bedroom to the airlock from the inside, inflate it, bring the stuff in to the bedroom. I'll also have to empty the bedroom of all tools and equipment to fold it up any time I need to do an EVA.
So yeah, it'll be annoying, but all it costs me is time. And I'm actually doing well on that front. I have 43 more sols before Hermes flies by. And looking at the procedure NASA has in mind for the modifications, I can take advantage of the MAV itself as a workspace.
The lunatics at NASA have me doing all kinds of rape to the MAV, but I don't have to open the hull till the end. So the first thing I'll do is clear out a bunch of clutter, like chairs and control panels and the like. Once they're out, I'll have a lot of room in there to work.
But I didn't do anything to the soon-to-be-mutilated MAV today. Today was all about system checks. Now that I'm back in contact with NASA, I have to go back to being all “safety first.” Strangely, NASA doesn't have total faith in my kludged-together rover or my method of piling everything into the trailer. They had me do a full systems check on every single component.
Everything's still working fine, though it's wearing down. The Regulator and Oxygenator are less than peak efficiency (to say the least) and the trailer leaks some air every day. Not enough to cause problems, but it's not a perfect seal. NASA's pretty uncomfortable with it, but we don't have any other options.
Then, they had me run a full diagnostic on the MAV. That's in much better shape. Everything's sleek and pristine and perfectly functional. I'd almost forgotten what new hardware even looks like.
Pity I'm going to tear it apart.
“You killed Watney,” Lewis said.
“Yeah,” Martinez said, scowling at his monitor. The words “Collision with Terrain” blinked accusingly.
“I pulled a nasty trick on him,” Johanssen said. “I gave him a malfunctioning altitude readout and made engine 3 cut out too early. It's a deadly combination.”
“Shouldn't have been a mission failure,” Martinez said. “I should have noticed the readout was wrong. It was way off.”
“Don't sweat it,” Lewis said. “That's why we drill. You've still got three weeks to get it right.”
“Will do,” Martinez said.
“We only got a week of remote launch training,” Johanssen said. “It was only supposed to happen if we scrubbed before landing. We'd launch the MAV to have it act as a satellite. It was a cut-your-losses scenario.”
“It's mission-critical now,” Lewis said. “So get it right.”
“Aye, Commander.” Martinez said.
“Resetting the Sim,” Johanssen said. “Anything specific you want to try?”
“Surprise me,” Martinez said.
Leaving the control room, Lewis made her way to the reactor. Climbing “up” the ladder toward the center of the ship, the centripetal force on her diminished to nearly zero as she reached the core. Vogel looked up from a computer console. “Commander?”
“How are the engines?” She asked, grabbing a wall-mounted handle to stay attached to the slowly turning room.
“All working within tolerance,” Vogel said. “I am now doing a diagnostic on the reactor. I am thinking that Johanssen is busy with the launching training. So perhaps I do this diagnostic for her.”
“Good idea,” Lewis said. “And how's our course?”
“All is well,” Vogel said. “No adjustments necessary. We are still on track to planned trajectory within 4 meters.”
“Keep me posted if anything changes.”
“Ja, Commander.”
Floating to the other side of the core, Lewis took the other ladder out, again gaining gravity as she went “down”. She made her way to the Airlock 2 ready room.
Beck held a coil of metal wire in one hand and a pair of work gloves in the other. “Heya, Commander. What's up?”
“I'd like to know your plan for recovering Mark.”
“Easy enough if the intercept is good,” Beck said. “I just finished attaching all the tethers we have into one long line. It's 214 meters long. I'll have the MMU pack on, so moving around will be easy. I can get going up to around 10 meters per second safely. Any more and I risk breaking the tether if I can't stop in time.”
“How fast a relative velocity can you handle, you think?”
“You mean once I get to Mark? I can grab the MAV easily at 5 meters per second. 10 meters per second is kind of like jumping on to a moving train. Anything more than that and I might miss.”
“So, including the MMU safe speed, we need to get within 20 meters per second of his velocity.”
“And the intercept has to be within 214 meters,” Beck said. “Pretty narrow margin of error.”
“We've got a lot of leeway,” Lewis said. “The launch will be 52 minutes before the intercept and it takes 12 minutes. As soon as Mark's S2 engine cuts out we'll know our intercept point and velocity. If we don't like it, we'll have 40 minutes to correct. Our engine's 2 millimeters per second may not seem like much, but in 40 minutes it can move us up to 5.7 kilometers.”
“Good,” Beck said. “And 214 meters isn't a hard limit, per se.”
“Yes it is,” Lewis corrected.
“Nah,” Beck said. “I know I'm not supposed to go untethered, but without my leash I could get way out there-”
“Not an option.” Lewis said.
“But we could double or even triple our safe intercept range-”
“We're done talking about this.” Lewis said sternly.
“Aye, Commander.”
LOG ENTRY: SOL 526
There aren't many people who can say they've vandalized a three billion dollar spacecraft. But I'm one of them.
I've been pulling critical hardware out of the MAV left and right. It's nice to know that my launch to orbit won't have any pesky back-up systems weighing me down.
First thing I did was remove the small stuff. Then came the things I could disassemble. Like the crew seats, several of the back-up systems, and the control panels.
I'm not improvising anything. I'm following a script sent by NASA, which was set up to make things as easy as possible. Sometimes I miss the days when I made all the decisions myself. Then I shake it off and remember I'm infinitely better with a bunch of geniuses deciding what I do than making shit up as I go along.
Periodically, I suit up, crawl into the airlock with as much junk as I can fit, and dump it outside. The area around the MAV looks like the set of Sanford and Son.
I learned about Sanford and Son from Lewis's collection. Seriously, that woman needs to see someone about her 70's problem.
LOG ENTRY: SOL 529
I'm turning my pee in to rocket fuel. It's easier than you'd think.
Urine is mostly water. Separating hydrogen and oxygen only requires a couple of electrodes and some current. The problem is collecting the hydrogen. I don't have any equipment for pulling hydrogen out of the air. The Atmospheric Regulator doesn't even know how. The last time I had to get hydrogen out of the air (back when I turned the Hab in to a bomb) I burned it to turn it in to water. Obviously that would be counter-productive.
But NASA thought everything through and gave me a process. First, I disconnected the rover and trailer from each other. Then, while wearing my EVA suit, I depressurized the trailer and back-filled it with pure oxygen at one fourth of an atmosphere. Then I opened a plastic box full of urine and put a couple of electrodes in. That's why I needed the atmosphere. Without it, the urine would just boil immediately and I'd be hanging around in an piss-based atmosphere.
The electrolysis separated the hydrogen and oxygen from each other. Over time, it reduced the urine to a really gross sludge as it pulled the water out. Now the trailer was full of even more oxygen and also hydrogen. Pretty dangerous, actually.
Then I fired up the Atmospheric Regulator. It doesn't even recognize hydrogen, but it knows how to yank oxygen out of the air. I broke all the safeties and set it to pull 100% of the oxygen out. After it was done, all that was left was hydrogen. That's why I started out with an atmosphere of pure oxygen. So the regulator could separate it later.
Then I opened the inner airlock door and had it evacuate the trailer. It pumped all the air in to the airlock's holding tank. And there you have it, a tank of pure hydrogen.