Music crept slowly into the brain of Venkat Kapoor. He rolled over in bed and put a pillow over his head to shut it out. The pillow failed to block his wife’s elbow in his ribs. Prodded into full wakefulness by spouse and ring-tone, he reluctantly pulled himself out of bed and groped for his phone. “Hello?”

“Dr. Kapoor? This is Mindy Park.”

“Is it PM or AM?” Venkat asked drowsily.

“I don’t know. I’m living on Mars time now,” Mindy said. “It’s mid-morning there. But the latest Mars satellite pics show Watney doing something weird. You’d better come in and see.”

Had Venkat been twenty years younger, the sleepiness would have fled instantly. But middle-aged scientists and high-level bureaucrats found sleep hard enough to come by even when the job wasn’t devouring them. “I’ll… be there shortly,” he said around a yawn. “But what can you tell me?”

“He’s rearranging the solar farm,” Mindy said. “He’s made a giant letter M so far. And the aliens are gathering rocks and piling them up just north of the solar panels.”

It wasn’t coffee, but the news made a decent substitute. “Keep everything you’ve got focused on the Hab,” he said. “I’ll be there in half an hour.”

Teddy flipped through the printed photographs, removing them from the paperclip one at a time and sliding each to the back of the stack as he looked at them. “Morse code,” he said. “Clever.” He made a face as he looked at the last panel. “Leet-speak? I thought we were done with that in the twenty-oughts. I always hated that garbage.”

“It does save on characters,” Mindy said quietly. “Um. And it takes a lot of rocks to make a message readable from space, even with maximum magnification and image enhancement.”

“’Alive Sol 32. Hit by antenna. Freak accident. Not crew’s fault. Better. Rations end Sol 307. Five aliens, food ends Sol 85, Sol 118 with Ares rations. Growing more.'” Teddy looked up from the page. “Sounds pretty bleak for the aliens.”

“Couldn’t he have told us more?” Annie asked. “We already knew all that shit except for the alien food situation.”

“It took him seven hours to lay that message out,” Venkat pointed out. “After he spent an hour moving the Hab solar cells to spell out MORSE. And he had help doing it.”

“And it took almost every rock within two hundred meters of the Hab to make,” Mindy added.

“Well, shit,” Annie snorted. “When will he make another message?”

“He probably won’t,” Venkat said. “He has no way of knowing when we see his message. He doesn’t even know we’re looking.”

“How can he not know?” Annie asked. “Of course we’re fucking looking! Who wouldn’t be fucking looking?”

“Ahem.” Teddy raised his hand. “Annie, if not for the aliens we wouldn’t have been looking. That was my decision and I own it, and I’m glad it wasn’t carried out. But Venkat’s right. Watney has no way of knowing that we’re watching him.” He tapped the paper in his hand. “But I’m most interested in the last two words. ‘Growing more.’ What do you think that means, Venk?”

Venkat shrugged. “I think it means he’s attempting to grow more food,” he said simply. “He’s a botanist. Before he applied to the astronaut corps he was doing field work in Africa reclaiming deserts.”

“It’s one of the reasons we accepted his application,” added Mitch Henderson from where he slumped in a chair.

“Do you think he can do it?” Teddy asked.

“I haven’t a clue,” Venkat said firmly, “but it doesn’t matter what I think. Watney thinks he can.”

“How would he go about doing it?” Teddy asked.

Venkat shrugged. “I can call in some experts if you like,” he said. “My guess is he’d take every container in the Hab, harvest water from the Martian permafrost, and try to build a hydroponic garden.”

“Um,” Mindy interrupted. “I don’t think that’s it. Remember all the EVAs Mark and the aliens did? We couldn’t figure out what they were doing? But they kept going to and from the airlocks. Maybe they were gathering topsoil.”

“That can’t be right,” Venkat said, shaking his head. “Martian soil is poisonous, and anyway the Hab’s not big enough for conventional agriculture.”

“Get in those experts,” Teddy said. “Have them check both scenarios. Ask them if Watney could get enough clean water for a hydroponic garden and if the Hab has enough materials to build one. Ask if Martian soil could grow crops, what Watney would need to do to make it work, and if the Hab could grow enough crops for six people.”

“Will do,” Venkat said, making a note.

Teddy turned to the speakerphone. “Bruce, how soon can we send a resupply mission to Mark?”

“Not soon,” the voice of Bruce Ng, chief of Jet Propulsion Laboratories, replied. “We’ve run rough scenarios ranging from a launch today through the next Hohmann window in twenty-one months. Right now is the worst possible time to send anything to Mars. It’d take four times the usual delta-V from Earth orbit to reach Mars, and nothing we send for the next four or five months will get there any sooner than maybe Sol 570.”

“Talk me through it,” Teddy insisted.

“Right now Earth is ahead of Mars in their orbits around the Sun,” Bruce said. “A direct flight would require cancelling Earth’s orbital momentum and offsetting solar gravity in addition to the acceleration required to reach Mars. Nothing mankind has ever built could do that. So instead whatever we launch has to go up like a mortar, way above Mars’s orbital path, to allow Mars time to catch up in its orbit. The probe would then encounter Mars on its path back down towards the Sun.”

“What are the numbers if we do that?” Teddy asked.

“Still lousy, but doable at least,” Bruce replied. “Launching today, like I said, would take four times the delta-V from orbit that our supply missions usually use. The heaviest lifter we currently have available is the Eagle Eye 3 probe’s booster. Launching today, it could land a three hundred kilogram payload on Mars.” The speakerphone went silent for a moment as Bruce paused for breath. “Note that’s not three hundred kilograms of food. That’s three hundred kilograms of food, the thing the food rides in, and the landing system that gets the food down intact and on target.

“The delta-V numbers improve with every day that passes, because we have to cancel out less and less of the Sun’s gravity on the trajectory. By the time we could actually launch- say in one hundred days- the potential payload goes up to nine hundred kilograms. Again,” Bruce’s voice warned, “that’s probe and food put together.

“But the really bad part,” Bruce finished, “is that the trajectories all end up with an arrival date somewhere between Sol 570 and Sol 610. Nothing we do with Eagle Eye will make that any faster.”

“Keep working the problem,” Teddy said. “If necessary plan for a double resupply mission. We’ll find another booster somewhere. But we need to find some way to get more food to him as soon as possible.”

“It’d help if I knew how large a resupply we were sending,” Bruce pointed out.

“That’s something that confuses me about Watney’s message,” Venkat added. “He says he has food for three hundred days. We already figured that by himself, if he rationed his food, he could last until Sol 400. But he also says that the aliens will run out of food on Sol 85, and then he says ‘Sol 118 with Ares rations.’ But the math doesn’t work. There must be some reason why the aliens only last until Sol 118 but Watney lasts until Sol 300.”

“Maybe ET has a food allergy,” Annie tossed off irritably.

“That’s a good idea,” Teddy said.

“The fuck you say!” Annie snapped. “It was a joke!”

“I’m serious,” Teddy said. “Maybe there’s only a few Earth foods the aliens can eat. Venk, have the Ares dietician go through the surface supplies for Ares III and categorize all the meals for known allergens and by general food type. You’re looking for something that makes three-quarters of the Ares meal packs unsuitable for aliens.”

Venkat made another note and kept quiet. He’d intended to do that anyway, but it never hurt to get your boss’s backing. It especially didn’t hurt when things played out so that the boss thought it was his idea.

“But getting back to the food,” Teddy continued. “The best analysis we have of orbital photos of Watney’s guests suggests that they have similar mass to humans. So assume similar food requirements. Six people, enough food to last until supplies can arrive in the next normal Mars launch window.”

“That’d be Sol 856,” Bruce said. “Let’s assume the probe arrives on Sol 556, I don’t know how. Three hundred fifty days of rations to provide a margin, for six people, at one kilogram per day, is twenty-one hundred kilograms.” The phone just barely picked up the JPL chief whistling through his teeth. “Eagle Eye 3’s Delta IX isn’t going to cut it. How soon can we get SpaceX to prep a Red Falcon first stage?”

“I’ll ask, but don’t get your hopes up,” Teddy said. “When I spoke with them last they were still backlogged on preparing for Ares IV presupply flights.” He paused, then flipped the last page in his hands and replaced the paperclip exactly as it had been when he’d received the photos, setting them down neatly on one corner of his desk blotter. “Speaking of Ares IV, there’s been a change in plans. The president has decided we’re not going to wait for Ares IV to rescue Mark Watney. The chance to make formal diplomatic contact with intelligent alien life makes the rescue mission urgent, assuming an alien rescue mission doesn't happen soon.”

“Excuse me?” Bruce Ng asked. “Does the president think we’re going to just drive there?”

“No. He expects us to take Hermes.” Teddy placed his hands on his desk and leaned forward. “Hermes will dock with the space station for refit in seven months. The next Hermes launch window is in twenty-one months. That gives us fourteen months to refit Hermes to support a crew of nine instead of six.”

“And how does he propose Watney and his friends get to Hermes?” Venkat asked. “The Ares III MAV is currently relaying satellite signals four hundred kilometers over his head.”

“Worst case scenario, he travels to Schiaparelli and uses the Ares IV MAV,” Teddy said. “Ares III-A can take a MAV to Mars to replace it, instead of an MDV. Alternately, if we can contact Watney, maybe he can use the Ares III MAV’s fuel plant to make enough fuel that a MAV can be landed at Ares III, fueled immediately, and launch.”

“I’ll try to find someone to run the numbers on that scenario,” Bruce said doubtfully.

“Don’t let it distract you from our top priority. Supplies for Watney first. Then rescue.” He turned to Mitch Henderson, who had kept unnaturally quiet for most of the meeting. “Mitch, I want you to pick a three-man flight crew for an Ares III-A mission. They won’t be landing, so we don’t need more crew. A pilot, a doctor, and a biologist. The most diplomatic astronauts we have- remember they’ll be dealing with intelligent alien life.”

“They’ll be dealing,” Mitch grunted, “with intelligent alien life that’s spent more than two years living with Mark Watney.”

“Good point,” Venkat said. “Better send a psychologist instead of a biologist.”

Everyone laughed except Teddy, who merely made a note on his blotter.

Sighing, Venkat doodled on his own notepad. “Hermes was built to last a minimum of five missions,” he said. “With regular refits it’s rated for thirty years. And its life support margins are broad enough that the only issue with nine crew would be crowding. It’s doable.”

“Why not just send the Ares-III crew back out again?” Henderson asked. “Lewis, Martinez and Beck, anyway. They have extra motivation to see Watney home safe.”

Teddy shook his head. “When they get home they’ll have been in space a year,” he said. “They need rest and recovery time, not training for a new mission as soon as they touch down. Better a fresh crew. And besides,” he added, leaning on his desk again, “every astronaut in the world already has all the motivation anyone can ask for to bring Watney home.”

Every head nodded agreement with that.

AMICITAS: Amicitas calling Baltimare, over.

AMICITAS: Amicitas calling Baltimare, over.

AMICITAS: Amicitas calling Baltimare, over.

ESA: Baltimare calling Amicitas. You’re early, over.

AMICITAS: Ready for large amounts of water, over.

ESA: Detailed description of flight and landing. Include any conclusions you have formed. Over.

AMICITAS: SG - Flight normal until mid-morning day 2. System fail-safe shutdown accompanied by shattering of all main engine batteries. Only two emergency magic batteries survived. All locally magic-powered systems shut down due to lack of environmental magic. Performed controlled crash forty minutes later using magic reserves in emergency batteries and thruster batteries. Conclusion: unexpected teleport into parallel world without universal magic field. Over.

ESA: Repeat no universal magic field? Over.

AMICITAS: SG- Confirmed. Only source of magic here is life-field. Currently only life on this planet is Amicitas crew, one alien, few plants. Over.

ESA: Understood. Time check your location? Over.

AMICITAS: DF – One hour before noon local time. Planet’s day longer than normal. Over.

ESA: Copied. Prepare for long message tomorrow beginning twenty-one hours from now. Over.

AMICITAS: DF – Will empty the buckets for you. Out.

Author's Notes:

I actually contacted Andy Weir on Facebook for this problem- not mentioning ponies. He didn't say more than to point out there are multiple possible trajectories for any flight that would get to Mars from any given point, so simulating them all isn't something a simple commercial app will do well. I didn't push farther than that.

So, instead, I went to a "well I killed a Kerbal so I'm bailing out" old save of KSP and used it to get delta-V changes for a ship from Kerbal (Earth) to Duna (Mars). Fuel expenditures for direct ascent with Earth just past Mars in orbit were astronomical- almost as much delta-V as was required to get from the surface to low orbit. Waiting even a hundred in-game days reduced the burn cost by almost half, but still way above the minimum requirement you'd get in a Hohmann lineup.

However, all three cases I tried ended up with almost the same arrival time, within ten to fifteen in-game days. Trying to make intercept happen sooner required so much extra thrust that it just wasn't plausible. The reasons are what Bruce Ng points out here: the more directly out your trajectory is from the Sun, the more thrust is required to overcome both solar gravity and Earth's existing orbital momentum. Hohmann windows are ideal because they're the points at which you essentially leave Earth at the same vector as it's traveling in its orbit, but faster, which efficiently widens your orbit without the need to cancel out or add to that existing momentum.

The variables involved are final payload to destination, total specific impulse of the craft involved, and how long you're willing to wait to get the payload there. They're all interconnected- the smaller the payload, the faster a set specific impulse will get you there. Currently the NASA bunch are finding that none of their numbers add up to food in time to do any good for Watney (let alone his visitors).

BTW, the dietician will require maybe five minutes to figure out why the food doesn't add up. No other possible factor in the menus sent up could add up to 25% except the vegetable-protein meals. So you're not going to get a scene referring to that until long after the fact.

SpaceX was not much more than a billionaire bragging in 2011 when the book was first written. In the movie SpaceX's name appears on Hermes. I'm bringing in SpaceX here to explain why their rockets aren't available for Watney's lunch pail. (Side note: I originally named the BFR "Blue Falcon", but a reader pointed me to Urban Dictionary, and I've changed it to Red Falcon even though that loses connection with the BFR joke. I'm still thinking Elon Musk will go with Blue Falcon if he keeps the initials, though.)

In the book Watney assumes nobody on Earth knows he's alive until Pathfinder connects with Earth. I see no reason to change that assumption now.

Mitch is JSC Mission Control flight leader, not head of the astronaut office, but in the book he essentially serves both roles. He's the main advocate for the astronauts. I'm maintaining that role in my story.

I haven't written anything yet today- usually I write before I post- but I have business work that absolutely needs finished today, and I should have begun on it four hours ago as it is. I'll try to write a short bit tonight.