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14

Marshall rubbed at his eyes, chasing away mounting fatigue. How long had he been at this? Stupid question, he decided, and counterproductive as well: The only question that mattered was how long had the Jiangs been out of contact with Earth? Their lives now came with fixed expiration dates.

Of the many cold, hard truths about working in space they’d tried to teach him in school, the crush of time was the one he now felt firsthand. Of all the esoteric and sometimes confounding displays aboard a spacecraft, one of the simplest and most indispensable was the master mission clock.

It governed every aspect of shipboard life. Every maneuver, which simply put was burning the engines for a specific amount of time at a specific power setting along a specific vector, was defined by time: when, and for how long, measured to the fraction of a second. If they needed the ship in a specific point in space, its arrival had to be worked backward to the second where they could begin burning engines. There would always be some point on the clock where they had to take action or miss the opportunity entirely. If it were a simple matter of changing their orbit around Earth, then missing a window meant waiting ninety minutes for it to come around again.

Leaving Earth entirely was a bit more complicated.

Which made Marshall wonder why the skipper had put him on it. Were the more senior officers that overwhelmed? Because this was way too important to just be some make-work exercise for the new guy.

Ours is not to reason why, he told himself. Ours is but to do or die. And please do try to avoid that last part.

The XO had given him a hard deadline, essentially twelve hours from Poole’s briefing, when they were to rendezvous with the propellant depot in LEO. By the time they had tanked up and the evac shuttle had left with Lesko and the others, they were expected to get underway and Commander Wicklund wanted hard figures for Poole long before they arrived. The XO had made it clear that he and the master chief were going to be neck deep in logistics planning with the other division officers, and he was relying on Marshall’s recency of training to carry the day.

“You just had this stuff in the last six months,” he’d said. “For the rest of us, it might as well be theoretical. We’ve been too busy working up here to even think about doing a run like this, whereas you’ve devoted some time to the idea. So get to it, mister.” Nobody at the academy had warned him that cadet research papers could come back to bite so hard in the ass once they were out in the fleet.

The XO had been just as unsparing in his critique of Marshall’s first-pass calculations. “Too conservative,” he’d said. “The first critical event comes in ten days when their hab’s internal air supply runs out. We do not want to get there a day late. This ship can do a lot, but she has her limits. Find them, then find me a way to move them.”

Find the limits, like it was a first-semester calculus problem. Marshall ran a tense hand through his bushy black hair and wished he could’ve had an actual desk to sit behind. Working these problems with a tablet and notepad Velcroed to the wall of his sleeping berth was not conducive to concentration.

Prospector should have been on a free-return trajectory, taking advantage of RQ39’s current proximity to take some pictures and measurements, then continue on an ellipse that ended back on Earth.

The cold truth was a satellite could have done the same thing for a lot less money but the Jiangs had bigger dreams. They wanted to show it could be done, see it for themselves, and explore it. Exploit it, really, but the exploration had to come first. If it was as full of rare-earth minerals (and what could be more rare-earth than something not from Earth) as they believed, then it was worth the risk of matching its orbit to stop and look around it for a while.

The opportunity came roughly every four years, which in their minds made it all the more urgent—for what if they missed this opportunity, who else might come out four years hence to stake a claim? RQ39’s synodic period put it within relatively easy reach on a cycle that could conceivably be exploited by humans, so the Jiangs had been out to prove an operating concept as much as to explore a near-Earth asteroid.

That wasn’t making his current job any easier. Borman’s nuclear-thermal powerplants gave them options that Prospector’s chemical engines didn’t, but it didn’t change the fact that the optimal departure window had closed three weeks ago. They were going to have to expel a lot of energy to get there before that “first critical event,” in order to reach a target that was flying farther away with each passing day. Then they’d have to burn again to slow down for a rendezvous, burn once more to accelerate back to Earth, then again to decelerate. There were some elegant tricks he could play that took advantage of Earth’s gravity to bend their trajectory, but in the end they’d have to slow this beast down enough for the planet to catch them—otherwise they’d be flung back out on a long ellipse that might as well have been as remote as RQ39’s.

It was just too much mass to move around. If time was the indispensable measurement, mass was the inescapable limitation.

What if it wasn’t? Poole had said they were going downhill to refuel and shed mass. So how much was he willing to shed? The XO hadn’t given him any insight. What about Garver?

Marshall opened up a message window on his tablet: HEY MASTER CHIEF. YOU UP?

He replied after a moment: IS THAT SUPPOSED TO BE A JOKE, SIR? COB IS THE ONLY BILLET ON THIS TUB THAT GETS LESS SLEEP THAN THE SKIPPER.

Point taken, he thought. JUST TRYING TO BE POLITE. I HAVE QUESTIONS. GOT A MINUTE?

Garver must have been thinking along the same lines: YOUR PLACE OR MINE?


The master chief’s sleeping compartment, which was still too small for Marshall to seriously consider calling “quarters,” felt lived-in to the point where he wondered if he would ever be that comfortable aboard. Every square inch of the wall opposite Garver’s sleeping bag was covered with photos arranged in a deliberate pattern. In the center were pictures of his family: his wife and sons, who appeared to be budding teenagers. Surrounding it were images from his time both above Earth and beneath the sea: submarines and spacecraft, dive suits and space suits.

Marshall tried not to be distracted by the panoply of colors; if he didn’t focus on them the hues and patterns came to resemble a quilt hanging above his bed. He realized that was precisely why Garver had arranged them so.

“So what’s troubling you, Ensign?”

Marshall found an empty area of sidewall for his tablet and notes, deciding to not waste his time with pleasantries. “I can’t make the numbers add up. We have the delta-v to get there in eight days, but not if we want to rendezvous and return.”

Garver rubbed his nose as he scrolled through the results. He paused at a graph of velocity change versus time: a series of irregular, concentric shapes bisected by diagonals, each representing a different period of days and total energy needed. “I see your point. Had a feeling that’s what you’d get hung up on. So you’re wondering about our mass budget.”

“I am.”

“As you should be,” Garver said. “As am I. As the skipper is, though he’s smart enough to not show that in front of the crew.”

“Would he want you telling me that?”

Garver smiled. “You’re assuming he told me that. I’m only guessing based on his actions and body language. HQ wrote a very large check and it’s up to him to figure out how to cash it.”

“Up to us, you mean.”

“Yes, that’s precisely what I mean.” He tapped at the graph’s eight-day line. “So this is our target, nonnegotiable. We have to figure out how to fit the mission inside of that energy budget.” He eyed Marshall. “You believe you’ve run out of ideas.”

“I don’t know how many I had to begin with, Master Chief.” Marshall sounded defeated.

“Good thing you came to me and not one of the other officers,” he said. “Because I, sir, do not care one whit about who gets credit for what. At least not among the officers. So what are your mass assumptions?”

“I started with standard loadout, but it became obvious that wasn’t going to work.”

“Could’ve told you that without even sharpening my pencil, sir. Only way we’re getting there with a full boat is on a Hohmann transfer, which would take too long, and we’ve missed the window anyway.”

“Right,” Marshall said. “So then I looked at limiting consumables to the expected trip duration. That has its own drawbacks.”

“You mean the part where if we have to stay longer, we run out of air or starve? It’s still viable, though. If we stay out there too long, at some point we’re not coming back within any kind of realistic timeframe. There’s your upper limit on consumables.”

“I thought about that. It still doesn’t move the ball far enough.”

“So you’ve trimmed all the fat. Now you’ve got to figure out which cuts of meat we can do without.”

“I was hoping that’s where you’d come in.”

“I have some thoughts.” Garver smiled, and pulled out his own notes. “We draw down to a skeleton crew. Not only does that save a hundred-ish kilos per body, it’s a big cut out of our ration budget.”

“You read my mind, Master Chief. But I’m not savvy enough to know how many crewmembers we actually need.” It would be about much more than raw numbers: who stayed on mattered.

“Don’t worry about that part, Mr. Hunter. I’ve already worked up a proposed roster.” He tapped Marshall’s graph, adjusting it for the new entry. “It still doesn’t get us far enough, though.”

Marshall scratched at his head, exasperated. “And this is where I hit the wall, Chief. I don’t see what else we can shed.”

Garver’s eyes glinted with the satisfied look of a tutor leading his student to a revelation. “What’s the mission, sir?”

“The mission? Intercept Prospector, rescue the Jiangs, and bring them back to Earth.”

“Any threats we should be worried about?”

“Another coronal mass ejection. Getting holed by a micrometeoroid. Major system failure . . .”

“All true, sir, and all wrong. I’m talking about hostiles. Do we expect to encounter any?”

Marshall’s eyes widened. That had been so far down his priority list as to put it out of his mind entirely, and Garver’s question was a stark reminder to not let that happen. “Well . . . no. All the potential threats are milsats in Earth orbit, not that we’ve ever had to engage any. There’s nothing out there but some stray boulders and a lot more nothing.”

“And is that something we need a full weapons loadout for?” Garver prodded further. “Vaporizing any rocks that might get in our way?”

The light went on in his head. “That’s a lot of mass we’re lugging around.”

“Indeed it is. Nearly all of it is for self-defense, and I’m not seeing what’s out there to defend against.”

Marshall thought about that. “We’d want some point-defense rounds for asteroid deflection in case we run across something uncharted. Say half a load. Maybe keep a couple of the ASAT interceptors in case we need to make something big disappear.” He paused. “Would Captain Poole be good with that?”

Garver stretched and stared at his wall of photos, eyes focusing on one in particular as if it held the key. It was an old one, of him and Poole from their Navy days with a group of others Marshall didn’t recognize, some of whom looked to be kitted out like SEALs. “It won’t be an easy sell, but if it accomplishes the mission, then yes.”

“A skeleton crew in an unarmed ship, taking it farther than it’s ever been,” Marshall deadpanned. “Where do I sign up?”


The reality was that in being the most junior officer, Marshall was likely to be the first in line to get cut, but not the only. He’d realized this, but now that they were presenting their findings to Poole he felt the press of the other officers’ eyes at his back for the first time. Not only was the new guy sticking his neck out, he was exposing others to the same fate.

“What does cutting this much of the crew do for our consumables?” Poole asked, though Marshall suspected he knew the answer.

“Over six and a half kilos per person, per day,” Marshall said.

Commander Wicklund approximated standing by Poole, his feet in a set of restraints and hands clasped behind his back. “Exact numbers, please.”

“Six point five-five-four,” Marshall said. “Apologies, sir. I thought it best to be conservative.”

As was his way, the XO was unsparing in his critique. “This is not the time for padding figures, Mister Hunter. Tell us precisely what conditions we need to meet, and precisely what we can do to meet them. The captain will decide the rest.”

Poole went a little easier on him. “Normally I’d say you’re right to be conservative, but first let’s work it down to the gnat’s ass like the XO said. Then maybe we can start adding back mass.” He rubbed his ball cap across his bald head as he looked for holes in their plan. “So we’re eight days out, assume two days on station, maybe ten back?”

“We can save propellant on the return leg using a lower-energy trajectory,” Chief Garver noted, “but then we’re trading off consumables again.”

“More time in transit equals more food and water,” Poole agreed. “Especially if we have survivors to feed. We’re not going to assume they’ve reached room temperature yet.” He eyed them both. “Is that clear?”

Marshall spoke for them. “Aye, sir.”

Poole pulled his cap back on, smoothing out the brim. “And by that logic, we can’t plan on shaving propellant mass to take the scenic route home. If they’re alive then they’re probably going to need medical attention, so we plan to expedite.”

“Our plan assumed the same, sir. We hadn’t looked to save weight in medical stores.” Marshall pointed to another equipment roster.

“We may have to consider that,” Wicklund noted. “How many units of blood plasma do we need for two evacuees? How many liters of saline?” He was fixed on Marshall. “If you haven’t looked to cut mass out of medical, then you haven’t spent enough time with Flynn or Riley. Your plan is incomplete, Mister Hunter.”

Marshall forced himself to keep his eyes fixed on the plotting board. “Understood, sir.”

If Poole was concerned about that, he wasn’t showing it. He tapped at his chin as he thought. There were other aspects he found more troubling. “Talk to me about the weapons loadout.”

Marshall shot a nervous glance at Chief Garver. “We keep the two ASAT interceptors already in their tubes and offload the rest,” he said. “We strip the magazines for the point-defense guns down by half. We can remove the small-arms locker but their mass ends up being so far inside the margin of error, Chief Garver convinced me it wasn’t worth the hassle.”

Poole nodded. “He’s right. It’s not. The fuel farm has racks for the big stuff so we can park it all in orbit until we get back. Side arms and carbines have to be signed for individually, packed away in a locked container, sent back to Earth on the shuttle, and secured in the armory at Vandenberg. Biggest pain in the ass over absolutely nothing . . .” he trailed off. They were meant for potential survival or escape situations in the event of an emergency return to Earth, which now was beside the point. “So yeah, those stay aboard. Never know when we might run into space pirates,” he deadpanned.

“We didn’t think you’d want to head out completely unarmed, sir.” Marshall drew his fingers across the plotting board, zooming out to their destination. “We’re concerned about uncatalogued NEOs in the vicinity, and as fast as we’ll be going—”

“If we detect one in our path, our only choice will be to blast it,” Poole agreed. “Instead of flying headlong into one big rock, we fly into a bunch of little rocks.”

“Our recommended tactical plan is to keep one of the ASATs hot at all times,” Marshall said, “with a continuous radar and lidar sweep along our vector. If we detect a collision threat, we destroy it with one of the interceptors and clean up any remains with the PDCs.”

“Creating even more little rocks,” the XO noted dryly. “We’d be trading one big hit for hundreds of little hits.” He turned to Poole.

Poole rubbed the bridge of his nose as he studied the images of asteroid RQ39. Could there be more like it nearby which just hadn’t been spotted yet? Hitting even a small one at over forty thousand kilometers an hour would be disastrous. “If it comes to that, it’ll be good gunnery practice.”

“That it will, sir,” Garver said with a grin.

Poole drew a breath. “Very well. Half magazines on the PDCs,” he said, “if you can make up the mass budget elsewhere.”

As Garver adjusted the mass estimate, it began to reach the threshold they needed. “That puts our C3 just over forty-six kps. It gets us there and back, sir, just barely.”

Poole frowned. “Yeah, I don’t like these margins. What else can you give me?”

Marshall searched his mind. He wasn’t sure how to answer that. What else could they possibly lose and still remain effective? “Maybe one or two more crewmembers, sir, but that only saves about three hundred kilos each. Offload one more ASAT, maybe strip one more belt of point-defense ammo . . .”

“Unacceptable,” Wicklund said. “We can’t break orbit with that thin of a loadout. The inertia reels feeding the cannons become unreliable if there’s not enough mass behind them to counterbalance. Even an empty belt on the other side is better than nothing.”

“Aye, sir,” was all Marshall could say, and made a mental note of it—one more example of exactly how much he still had to learn about this ship.

Poole swiped at the plotting board, his eyes following their elliptical orbit to intercept Prospector. “Where’s the Moon in this scenario?”

“Sir?”

“You raced gliders cross-country, right?” It was a subtle reminder to the others that young Ensign Hunter wasn’t exactly an unknown quantity to the CO. “You learned a lot about where to look for lift, I’ll bet.”

“Yes sir,” Marshall said warily, wondering where Poole was going with this. “Sometimes you have to be creative to get where you’re going.” It was better to ride a column of warm air as high as possible before getting in a hurry to cover distance with unknown sources of lift.

Poole tapped the plot of their orbit and began dragging it in a different direction. “And a sailboat captain learns how to read the seas and tack into the wind, so he can get where he’s going even if the wind’s against him. We both use the environment to our advantage. If there’s a gravity well anywhere on our way out, we can exploit that. And we’ve got two right here.” He tapped on the Earth and the Moon.

“You mean a slingshot—er, gravity assist, sir?”

The XO corrected him. “He means an Oberth maneuver. Similar, but different.”

Poole arched an eyebrow in Marshall’s direction. “Your old man showed me what a good spacecraft driver does a long time ago, Mr. Hunter. Took us around the Moon hell-for-leather, he did. By the time we reached periapsis he had me closing my eyes and hoping we didn’t scrape lunar dirt.”

He did? “Begging your pardon, sir. I knew you were with him at the Gateway incident.” Marshall swallowed. “He just never shared any of the details.” He grew quiet. He didn’t notice the looks Poole exchanged with the XO and chief, patting the air with his hand to dissuade their concern.

Poole laid a hand on the young man’s shoulder. “Maybe later, when we’re back on the beach.” He looked up at the XO and chief. “It’s a hell of a story, gents.” He decided it was time to take the pressure off their newest officer. “Good work, Mr. Hunter. Not perfect, but a good start.” He pointed at the plotting board. “The trick with a gravity assist is the gravity part. The deeper the well, the bigger the multiple. And the closer you can get to the bottom of that well, the greater your mass effect.”

Their path was an ellipse beginning at Earth and curving tightly around RQ39, with arrows at numerous points along the way to mark critical events. “Sometimes when nature doesn’t cooperate, the fastest route to your destination is to start in the wrong direction.” He pulled the ellipse out toward the Moon, then back to Earth. “We climb up the well to the edge of Earth’s Hill sphere, then let ourselves fall back. We’re picking up velocity on the way down. We do a gravity-assist burn at the bottom and whip around Earth’s backside, outbound to RQ39.” The path from there grew straighter, reflecting their increased speed. “The other thing we can do is burn one hydrogen tank at a time instead of drawing from all three equally.”

The XO leaned in. “I think I see where you’re going, sir. Punching empty tanks will create some trim problems.”

Poole waved it away. “Nothing we can’t handle. You guys are smart enough, I think.”

“Begging your pardon, sir, but I’m not following,” Marshall said.

Poole explained. “We have too much mass to move quickly without having to expend just as much energy when we arrive. The lighter we are, the less we have to expend. So we’re going to burn the outboard tanks first and jettison them when they’re empty.”

“The bean counters will scream bloody murder,” the XO warned. “That’s a heavy-lift launcher to replace each tank.”

“Good thing Logistics isn’t running this op,” Poole said. “If we don’t reach Prospector before the first critical event, Ops will be pissed. Either way, some staff officer’s going to be pissed which means we’re doing something right.” Poole eyed the chief. “Garver, just make sure we don’t do anything stupid like bomb rural Nebraska with an empty hydrogen tank.”

“I’m from North Platte, sir. It’s all rural,” the chief reminded him. “I’ll make sure we time it just right, Skipper.”

Poole adjusted for their new mass estimate, which now landed squarely within their energy budget. “We’ll drop the other outboard tank after our braking burn.” They had too much mass to move so quickly without needing to expend just as much energy when they arrived on station—they wouldn’t be doing the Jiangs any good if they shot past without slowing down enough to match orbits. “Not like we can tie a life preserver to a line and throw it out there.”

“Would that it was true, sir,” Garver said.

“And since tractor beams don’t exist yet . . .” Poole mused, cheerful and satisfied that the pieces had come together. “Very well, gentlemen. This is a solid plan.” He turned to Wicklund and Garver. “XO, put it into action. Give me sitreps every four hours. Chief, I’m assuming you already have a roster for me?”

“Affirmative, sir,” he said, and swiped at his tablet to send the crew manifest to Poole’s.

He studied it silently, his face a mask of impartiality. The CO was not giving up any clues as to whether the chief’s recommendations made him feel anything. After a minute of contemplation, he looked up at them. “I’d only change one thing: take your own name off the cut list. You’re going, Chief.”

Before Garver could offer an alternative, Poole cut him off. “Spare me any bromides about avoiding the appearance of self-dealing. The only swinging Richard with more time on this tub than you, is me.” He stabbed at the tablet. “If we’re drawing down crew by half, then the remaining half had better be locked on.”

That led him to Marshall. “I’m sorry, son. That means you’re on the cut list.”


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