Delta-v, page 27
Mission controllers launched three cube sats from racks on the Konstantin’s spine, placing them in different orbits around Ryugu to act as communication relays.
By the first evening, the crews in both habs sat around their galley tables for dinner, using the AR conference system to virtually extend their four-person tables into one eight-person gathering. Lacroix and the other mission control managers also joined them via a virtual video.
Lacroix led a toast as the crew held up plastic cups of rehydrated apple juice. Awkwardly, they received his words nearly a minute later. “To humanity’s next great leap.”
“Hear! Hear!”
After dinner Captain Clarke activated the Konstantin’s exterior lights, kicking on a million-lumen searchlight located on the lower spine of the ship. The brilliant beam stabbed out at the asteroid’s surface, landing as a small but brilliant ellipse. Shadows played across the irregular regolith as the beam searched.
Sitting in the galley of Hab 1, Tighe, Abarca, and Jin watched a virtual screen showing a close-up of the beam’s span. Clarke guided the searchlight through the coordinates of surface boulders ranging in size from 8 to 4 meters in diameter, chosen from 2018 Hayabusa2 mission imagery and current radar scans. She worked through a list of candidate rocks supplied by mission control—boulders that looked easy to separate from the surface and enclose in one of their 15-meter asteroid bags.
Due to Ryugu’s slow rotation, it took more than seven hours to lay eyes on them all. Afterward, Clarke and mission control geologists narrowed the list to only six candidates for follow-up muon tomography scanning—which would confirm that the boulders did not extend deep into the regolith.
The crew went to bed just after one a.m. UTC.
As Tighe lay in his cot, he was so excited that he could barely close his eyes. He was in deep space, alongside Ryugu, and still alive. Tomorrow they would try to do something no one had ever attempted: harvest water in deep space. He smiled as he recalled the breathtaking view outside the ship, then grabbed his crystal to check the countdown:
211 hours, 4 minutes until the return window to Earth closed.
If they could not derive the necessities of life from this mountain of dust within the next nine days, they would need to head home.
The failure of the expedition would spell financial ruin for Joyce, of course, but that didn’t seem all that important. Tighe suspected people like Joyce would always find a way to be rich. What did concern Tighe was what their failure would mean to the future of exploration. How long until someone tried again? Decades? A century? Would it even be possible ever again?
They must succeed. There was no other choice.
Tighe finally fell into a restless sleep, his dreams filled with visions of falling down a cliff face back on Earth—as Abarca, Morra, Jin, and the others gazed down on him from a high ledge.
* * *
—
Tighe was awakened at six a.m. by mission control playing music throughout both habs—the guitar riff, horns, and strings of “Papa Was a Rollin’ Stone.” Tighe and Morra got up and stretched as the overhead lights came up.
Morra glanced at the ceiling. “I get the stone analogy, but does mission control realize it’s meant as a metaphor for bad parenting?”
“Pretty sure that’s not what they were going for.”
Not much later Abarca, Tighe, Morra, and Clarke sat around the galley table sipping freeze-dried coffee and eating rehydrated oatmeal. Mission control managers appeared on a video feed—with one of them standing in front of a green screen of Ryugu, pointing out key surface features like an off-world weatherman.
The other four crew members from Hab 2 beamed in via the AR link, and thus appeared to be having breakfast on an extended virtual table in the wall alongside them. It was a surreal caricature of a normal household starting their day.
A virtual Adisa looked up from a UI only he could see. “We are 215,000 kilometers farther from Earth than yesterday. Relative velocity is, for the moment, 8,941 kilometers per hour and will reduce slightly each day for some time.”
Abarca glanced up from reading. “Which means what to us, Ade?”
“Which means the communications delay with Earth will increase by roughly a second and a half every day for the next several months. Today it is forty-eight seconds—with a mission control response time of ninety-six seconds. I can place the current comm delay in the lower left corner of the group main screen, for ready reference, if that is helpful.”
Clarke nodded. “That is useful, Ade. Thanks.” She looked over her bowl of oatmeal to a virtual Chindarkar, who was also tapping at invisible objects while sipping tea. “Priya, this morning I’d like you to take the muon tomography scanner and get detailed subsurface maps of our boulder candidates. We’ll regroup with mission control once you have that data.”
“You got it.”
Adisa spoke to Chindarkar. “Priya, please use Mule 3 or 1. The other two have error codes I am still tracking down.”
Chindarkar looked to Clarke. “Which boulder do you want me to start with?”
“Whichever’s closest when you launch.” Clarke spoke through a comm link. “Mission control, we’re preparing a mule for surface scanning. If you have suggestions, now’s the time.”
Everyone knew an answer wouldn’t be coming for another minute and a half.
Clarke turned to Tighe, Morra, and a virtual Jin. “Mission control wants us to hook up the magnetic rake and try to harvest enough regolith for an initial assay. They’ve marked a promising iron-rich dust pool on the coordinate grid. Han, you’re on the pilot roster today. Dave and J.T., you manage the rake.”
Tighe perked up. “EVA?”
“Negative. Telepresence only. No unnecessary radiation exposure. Let our machines do the work. Use a mule .”
“Any Valkyries?”
“One Valkyrie. And keep it clamped to the running board unless absolutely necessary. Return to the ship when you’ve got at least fifty kilos of regolith—the most representative sample you can find.”
“Aye, aye, Captain.”
Morra spoke to Jin’s AR image. “Han, conference us after breakfast.”
“I’ll be there.”
After eating, Tighe and Morra headed down to their workstations. There, Tighe jacked in to the 3D telepresence system with his crystal and could see that Chindarkar had already checked out Mule 3, leaving Mule 1 as the only green-status unit. He glanced up to see Morra slip in to the chair of the workstation opposite, a cup of tea in his hand.
Tighe spoke while manipulating the holographic UI floating between them. “And to think my entire life has been one long effort to avoid working in a cubicle. . . .”
“I reckon most people would be jealous, mate.”
Tighe spoke through the comm link. “Priya, we’ll wait until you’re clear of the dock before we power up.”
“Grabbing the scanner now. I’ll just be a minute.”
“Take your time. Jin, you with us?”
Jin’s voice came in over the comm link. “I am here.”
Tighe looked to Morra. “You want the Valkyrie?”
Morra raised his mug. “You take it. Royal Engineers will act in an advisory capacity this morning.”
“Han, Dave’s got the jitters, so it looks like I’ll be your Valkyrie.”
Morra chuckled. “Wanker.”
“Come by and pick me up. I’m Unit”—Tighe examined a row of Valkyrie icons—“V-2.”
“Unit V-2. Copy.”
Tighe tapped Unit V-2 in his display. After a brief delay his crystal became a virtual reality headset, filled by a first-person view of the Valkyrie’s stereographic cameras. It was fully immersive, and just like yesterday the starscape was spectacular.
“I don’t ever want to get used to this.” Tighe turned his robotic gaze upward to see Mule 3 silently navigating just overhead, its cold-gas thrusters popping occasionally. Tighe watched as the mule’s robotic arms grabbed the muon tomography scanner from the tool rack atop the ship’s docking port. The scanner was a box the size of a refrigerator. It detected “coulomb scattering” of subatomic particles to derive imagery inside solid objects. The same technology had been used to locate hidden burial chambers in the Egyptian pyramids.
After a few more moments, Chindarkar piloted Mule 3 away. “All yours.”
“Happy scanning.”
Jin then piloted Mule 1 in front of Tighe’s robot avatar. Tighe extended his real-world arm, and scanners on his desk transferred the gesture to his Valkyrie, grabbing the metal handle that ran along the length of the mule. Tighe undocked his robot from its charger and lifted the Valkyrie’s feet onto the running board, clipping its tether into an eyebolt on the mule’s hull. “I’m clipped in, Han.”
“Maneuvering . . .” The view shifted as the mule’s thrusters popped. Jin navigated to dock with the folded magnetic rake, locked down, and then pulled the tool free from its storage clamps.
Jin’s voice came over the radio. “Mule 1 ready to deploy rake.”
Clarke’s voice replied. “Roger that. Jin, I’ve marked the coordinates of Dust Pond 3 on your display.”
“I am maneuvering . . .”
The mule’s thrusters popped once more, and Tighe’s view turned toward the black shadow of the asteroid. The surface was 3 kilometers away on his readout. The mule thrust straight toward it, getting clear of the Konstantin’s rotating radial arms, the ends of which held blinking navigation lights. The three habs silently swept past at 124 kilometers per hour.
Tighe watched the dark wall of the asteroid approach. “This is pretty intense, Dave. You sure you don’t want to spectate?”
Across the desk an unseen Morra said, “Already am.”
Jin kicked on the mule’s bottom lamps and rotated Mule 1 so the rake faced Ryugu. It now seemed like they were descending to the asteroid’s surface, rather than gliding toward an immense wall.
As they got closer the mule’s lights began to illuminate a level, irregularly shaped area of regolith no bigger than a wading pool. It was bordered by low ridges of ashen rock.
Jin’s voice: “Mule 1 on station.”
After a brief pause, Clarke said, “Deploy the rake and proceed, Mule 1.”
Tighe lowered his real-world chin to have the Valkyrie look down at its feet. Below the mule the wire grid of the magnetic rake unfolded out to a 5-meter square.
“Rake deployed. Electromagnets . . . powered on.” The thrusters popped to gently lower the mule toward the asteroid. “Descending to Dust Pond 3.”
“Keep the mule above the regolith, Han. Mission control says Ryugu’s dark side has a significant electrical charge.”
“I copy.”
Tighe watched the approaching surface of the asteroid through the grid of magnetized wire. Illuminated by the mule’s work lights, the dust looked impossibly fine. “If that’s got iron in it, it should be easy to collect with a magnet.”
As the magnetic rake descended, particles suddenly coalesced along the lines of the magnetic field, making the dust almost seem alive. It swarmed around the wire grid and extended ferrous tendrils toward the mule’s running board.
“Look at that.”
Jin’s voice: “I’m getting pulled in.”
Morra’s voice: “Heads up.”
A blue bolt of electricity arced along the rake, and suddenly Tighe’s Valkyrie link went dead. His crystal went transparent again, and he and Morra stared at each other in the workstation.
Tighe keyed his mic. “Nicole, V-2 is down. Just lost my connection.” He opened Mule 1’s video feed, which skipped with signal interference but was still online.
Jin said, “The rake dragged the mule down into the regolith.”
Clarke answered. “Pop thrusters. Get the mule out of there.”
As the mule’s downward thrusters fired, the entire screen filled with blinding dust. Then the link to the mule was gone.
Jin’s voice: “Lost mule signal.”
“You have got to be shitting me. . . .”
But then it came back.
“Wait. I’m back up.”
Morra shook his head and groaned. “Oh, man. What are we doing . . . ?” He tapped at a virtual UI and brought up a distant CCTV image of the mule as seen from the Konstantin. “Jin, I think you should return to the ship.” He rewound the video and tapped “Play.” “Nicole, watch my video layer. . . .”
Tighe and Morra watched the recording as the distant mule’s work lights momentarily became obscured by a cloud of dust as its thrusters blasted downward. By the time the craft rose above the cloud, the rake was empty.
Morra spoke over the comm link. “Nicole, the rake is useless. When we turn on the electromagnet it pulls us in, and when we pop thrusters it creates a metallic cloud that acts like a Faraday cage—and also blasts the rake clean. It needs a redesign.”
Clarke replied, “How long do you need?”
“I’ll sort that out with Ade.” Morra closed the video window. “In the meantime, we could use the Archimedes’ screw to pull up a regolith sample. That should hold enough for an assay.”
“But would the screw cut into rock?”
Adisa answered instead. “Hayabusa2 data shows rock density to be low—1.5 grams per cubic centimeter. You could crumble it in your hands.”
Morra nodded. “Right. So we drill a core sample from a boulder. Bring it back to the refinery and cook it. The sooner we get a sample, the sooner we know whether this entire expedition is possible. The clock’s ticking.”
They all glanced at the countdown, hovering at the edge of their vision.
After a few moments Clarke said, “All right. Let’s do it.”
* * *
—
Two hours later Tighe and Morra again sat at their workstations watching a shared holographic display of Mule 1 hovering above a boulder on Ryugu’s surface. Except this time the mule had a different tool attached to its lower docking port. The Archimedes’ screw consisted of a polymer tube, 20 centimeters in diameter, inside of which was an aluminum auger, the sharp point of which jutted out like a corkscrew.
The mule’s work lights illuminated a massive boulder rising tens of meters above the surrounding terrain—high enough that the surface was mostly lost in shadow.
Jin’s voice came in over the comm link. “Twenty meters.”
The ashen, irregular surface of the boulder came into view.
Clarke said, “Aim for the highest elevation, Han.”
“Maneuvering . . .”
The mule popped thrusters as Jin piloted the vehicle in, guiding the auger tip. Thrusters fired course corrections occasionally. Finally, the auger touched down with the full mass of the mule behind it, penetrating the surface.
“Activating auger . . .”
The blade bit into the ashen rock and started sinking from sight. Ryugu’s rock appeared to be as porous as anticipated.
Jin’s voice came in. “We are getting regolith in the sleeve.”
Tighe and the others applauded. He and Morra high-fived across the workstation.
The auger began to sink deeper into the rock.
Tighe watched the hologram. “Why don’t we just keep doing this?”
Morra studied the image. “Burning 20 kilos of thruster gas to get 50 kilos of regolith isn’t exactly efficient.”
They watched for another minute or so until Clarke announced, “Jin, that should be plenty. Bring the core sample back to the bottom airlock and offload it into Pressure Vessel 1. Amy?”
Tsukada’s voice came over the comm link. “Here, Nicole.”
“Work with Jin to make sure the sample gets into your refinery. Tell me when you’re ready to begin the assay. I want every step on video for mission control.”
* * *
—
By early afternoon Tighe, Abarca, and Morra sat around the galley table as Clarke arranged virtual video windows to reveal every corner of the Konstantin’s refinery.
The refinery was located in the aft section of the ship, just forward of the engine room. Surveillance cameras showed branching groups of color-coded piping and conduits running in and out of a central chamber. Neither the refinery nor the engine room of the Konstantin was pressurized, to limit the risk of fire.
Like all of the crew, Tighe had been trained to process asteroid regolith—but up until now it was theoretical, only having been done with asteroid simulant back on Earth.
Clarke spoke over the comm link. “Amy, Gabriel tells me that Nathan Joyce is watching. So I want you to bring us through each step of the refining process. Understood?”
Tsukada replied, “Understood, Nicole. Stand by.”
A virtual window expanded, providing a view into what looked like an industrial clothes dryer with metal fins set into the walls. The chamber was filled with a cloud of floating ash.
Tsukada said, “Assay 1, Ryugu, January 31, 2034, 1321 hours UTC. Initial sample mass: 87.32 kilos. Note that the regolith sample has been pulverized to increase surface area for chemical reactions.” She was silent for several moments. “Spectrometer readings confirm composition consistent with carbonaceous chondrite—which is what Catalyst mission planners were expecting.”
Tighe, Morra, and Abarca applauded.
Clarke’s voice broke in. “I’m sure they’ll be happy to hear that, Amy.”
A reddish glow appeared in the interior of the pressure vessel.
“Heating sample to 500 degrees Celsius. This will cause the hydrates to release their volatiles—that is, chemical compounds with low boiling points.”
Tighe and the others watched a mist forming amid the dust.
“What you see being released here is mostly water vapor.”
Again the crew applauded and hooted.
“However, this vapor also contains impurities—ammonia, carbon monoxide, nitrogen, methane, hydrogen cyanide, hydrogen sulfide. We’ll need to filter these out using in situ chemical oxidation—fortunately I should be able to synthesize the hydrogen peroxide and potassium permanganate necessary for that from Ryugu’s regolith.”
By the first evening, the crews in both habs sat around their galley tables for dinner, using the AR conference system to virtually extend their four-person tables into one eight-person gathering. Lacroix and the other mission control managers also joined them via a virtual video.
Lacroix led a toast as the crew held up plastic cups of rehydrated apple juice. Awkwardly, they received his words nearly a minute later. “To humanity’s next great leap.”
“Hear! Hear!”
After dinner Captain Clarke activated the Konstantin’s exterior lights, kicking on a million-lumen searchlight located on the lower spine of the ship. The brilliant beam stabbed out at the asteroid’s surface, landing as a small but brilliant ellipse. Shadows played across the irregular regolith as the beam searched.
Sitting in the galley of Hab 1, Tighe, Abarca, and Jin watched a virtual screen showing a close-up of the beam’s span. Clarke guided the searchlight through the coordinates of surface boulders ranging in size from 8 to 4 meters in diameter, chosen from 2018 Hayabusa2 mission imagery and current radar scans. She worked through a list of candidate rocks supplied by mission control—boulders that looked easy to separate from the surface and enclose in one of their 15-meter asteroid bags.
Due to Ryugu’s slow rotation, it took more than seven hours to lay eyes on them all. Afterward, Clarke and mission control geologists narrowed the list to only six candidates for follow-up muon tomography scanning—which would confirm that the boulders did not extend deep into the regolith.
The crew went to bed just after one a.m. UTC.
As Tighe lay in his cot, he was so excited that he could barely close his eyes. He was in deep space, alongside Ryugu, and still alive. Tomorrow they would try to do something no one had ever attempted: harvest water in deep space. He smiled as he recalled the breathtaking view outside the ship, then grabbed his crystal to check the countdown:
211 hours, 4 minutes until the return window to Earth closed.
If they could not derive the necessities of life from this mountain of dust within the next nine days, they would need to head home.
The failure of the expedition would spell financial ruin for Joyce, of course, but that didn’t seem all that important. Tighe suspected people like Joyce would always find a way to be rich. What did concern Tighe was what their failure would mean to the future of exploration. How long until someone tried again? Decades? A century? Would it even be possible ever again?
They must succeed. There was no other choice.
Tighe finally fell into a restless sleep, his dreams filled with visions of falling down a cliff face back on Earth—as Abarca, Morra, Jin, and the others gazed down on him from a high ledge.
* * *
—
Tighe was awakened at six a.m. by mission control playing music throughout both habs—the guitar riff, horns, and strings of “Papa Was a Rollin’ Stone.” Tighe and Morra got up and stretched as the overhead lights came up.
Morra glanced at the ceiling. “I get the stone analogy, but does mission control realize it’s meant as a metaphor for bad parenting?”
“Pretty sure that’s not what they were going for.”
Not much later Abarca, Tighe, Morra, and Clarke sat around the galley table sipping freeze-dried coffee and eating rehydrated oatmeal. Mission control managers appeared on a video feed—with one of them standing in front of a green screen of Ryugu, pointing out key surface features like an off-world weatherman.
The other four crew members from Hab 2 beamed in via the AR link, and thus appeared to be having breakfast on an extended virtual table in the wall alongside them. It was a surreal caricature of a normal household starting their day.
A virtual Adisa looked up from a UI only he could see. “We are 215,000 kilometers farther from Earth than yesterday. Relative velocity is, for the moment, 8,941 kilometers per hour and will reduce slightly each day for some time.”
Abarca glanced up from reading. “Which means what to us, Ade?”
“Which means the communications delay with Earth will increase by roughly a second and a half every day for the next several months. Today it is forty-eight seconds—with a mission control response time of ninety-six seconds. I can place the current comm delay in the lower left corner of the group main screen, for ready reference, if that is helpful.”
Clarke nodded. “That is useful, Ade. Thanks.” She looked over her bowl of oatmeal to a virtual Chindarkar, who was also tapping at invisible objects while sipping tea. “Priya, this morning I’d like you to take the muon tomography scanner and get detailed subsurface maps of our boulder candidates. We’ll regroup with mission control once you have that data.”
“You got it.”
Adisa spoke to Chindarkar. “Priya, please use Mule 3 or 1. The other two have error codes I am still tracking down.”
Chindarkar looked to Clarke. “Which boulder do you want me to start with?”
“Whichever’s closest when you launch.” Clarke spoke through a comm link. “Mission control, we’re preparing a mule for surface scanning. If you have suggestions, now’s the time.”
Everyone knew an answer wouldn’t be coming for another minute and a half.
Clarke turned to Tighe, Morra, and a virtual Jin. “Mission control wants us to hook up the magnetic rake and try to harvest enough regolith for an initial assay. They’ve marked a promising iron-rich dust pool on the coordinate grid. Han, you’re on the pilot roster today. Dave and J.T., you manage the rake.”
Tighe perked up. “EVA?”
“Negative. Telepresence only. No unnecessary radiation exposure. Let our machines do the work. Use a mule .”
“Any Valkyries?”
“One Valkyrie. And keep it clamped to the running board unless absolutely necessary. Return to the ship when you’ve got at least fifty kilos of regolith—the most representative sample you can find.”
“Aye, aye, Captain.”
Morra spoke to Jin’s AR image. “Han, conference us after breakfast.”
“I’ll be there.”
After eating, Tighe and Morra headed down to their workstations. There, Tighe jacked in to the 3D telepresence system with his crystal and could see that Chindarkar had already checked out Mule 3, leaving Mule 1 as the only green-status unit. He glanced up to see Morra slip in to the chair of the workstation opposite, a cup of tea in his hand.
Tighe spoke while manipulating the holographic UI floating between them. “And to think my entire life has been one long effort to avoid working in a cubicle. . . .”
“I reckon most people would be jealous, mate.”
Tighe spoke through the comm link. “Priya, we’ll wait until you’re clear of the dock before we power up.”
“Grabbing the scanner now. I’ll just be a minute.”
“Take your time. Jin, you with us?”
Jin’s voice came in over the comm link. “I am here.”
Tighe looked to Morra. “You want the Valkyrie?”
Morra raised his mug. “You take it. Royal Engineers will act in an advisory capacity this morning.”
“Han, Dave’s got the jitters, so it looks like I’ll be your Valkyrie.”
Morra chuckled. “Wanker.”
“Come by and pick me up. I’m Unit”—Tighe examined a row of Valkyrie icons—“V-2.”
“Unit V-2. Copy.”
Tighe tapped Unit V-2 in his display. After a brief delay his crystal became a virtual reality headset, filled by a first-person view of the Valkyrie’s stereographic cameras. It was fully immersive, and just like yesterday the starscape was spectacular.
“I don’t ever want to get used to this.” Tighe turned his robotic gaze upward to see Mule 3 silently navigating just overhead, its cold-gas thrusters popping occasionally. Tighe watched as the mule’s robotic arms grabbed the muon tomography scanner from the tool rack atop the ship’s docking port. The scanner was a box the size of a refrigerator. It detected “coulomb scattering” of subatomic particles to derive imagery inside solid objects. The same technology had been used to locate hidden burial chambers in the Egyptian pyramids.
After a few more moments, Chindarkar piloted Mule 3 away. “All yours.”
“Happy scanning.”
Jin then piloted Mule 1 in front of Tighe’s robot avatar. Tighe extended his real-world arm, and scanners on his desk transferred the gesture to his Valkyrie, grabbing the metal handle that ran along the length of the mule. Tighe undocked his robot from its charger and lifted the Valkyrie’s feet onto the running board, clipping its tether into an eyebolt on the mule’s hull. “I’m clipped in, Han.”
“Maneuvering . . .” The view shifted as the mule’s thrusters popped. Jin navigated to dock with the folded magnetic rake, locked down, and then pulled the tool free from its storage clamps.
Jin’s voice came over the radio. “Mule 1 ready to deploy rake.”
Clarke’s voice replied. “Roger that. Jin, I’ve marked the coordinates of Dust Pond 3 on your display.”
“I am maneuvering . . .”
The mule’s thrusters popped once more, and Tighe’s view turned toward the black shadow of the asteroid. The surface was 3 kilometers away on his readout. The mule thrust straight toward it, getting clear of the Konstantin’s rotating radial arms, the ends of which held blinking navigation lights. The three habs silently swept past at 124 kilometers per hour.
Tighe watched the dark wall of the asteroid approach. “This is pretty intense, Dave. You sure you don’t want to spectate?”
Across the desk an unseen Morra said, “Already am.”
Jin kicked on the mule’s bottom lamps and rotated Mule 1 so the rake faced Ryugu. It now seemed like they were descending to the asteroid’s surface, rather than gliding toward an immense wall.
As they got closer the mule’s lights began to illuminate a level, irregularly shaped area of regolith no bigger than a wading pool. It was bordered by low ridges of ashen rock.
Jin’s voice: “Mule 1 on station.”
After a brief pause, Clarke said, “Deploy the rake and proceed, Mule 1.”
Tighe lowered his real-world chin to have the Valkyrie look down at its feet. Below the mule the wire grid of the magnetic rake unfolded out to a 5-meter square.
“Rake deployed. Electromagnets . . . powered on.” The thrusters popped to gently lower the mule toward the asteroid. “Descending to Dust Pond 3.”
“Keep the mule above the regolith, Han. Mission control says Ryugu’s dark side has a significant electrical charge.”
“I copy.”
Tighe watched the approaching surface of the asteroid through the grid of magnetized wire. Illuminated by the mule’s work lights, the dust looked impossibly fine. “If that’s got iron in it, it should be easy to collect with a magnet.”
As the magnetic rake descended, particles suddenly coalesced along the lines of the magnetic field, making the dust almost seem alive. It swarmed around the wire grid and extended ferrous tendrils toward the mule’s running board.
“Look at that.”
Jin’s voice: “I’m getting pulled in.”
Morra’s voice: “Heads up.”
A blue bolt of electricity arced along the rake, and suddenly Tighe’s Valkyrie link went dead. His crystal went transparent again, and he and Morra stared at each other in the workstation.
Tighe keyed his mic. “Nicole, V-2 is down. Just lost my connection.” He opened Mule 1’s video feed, which skipped with signal interference but was still online.
Jin said, “The rake dragged the mule down into the regolith.”
Clarke answered. “Pop thrusters. Get the mule out of there.”
As the mule’s downward thrusters fired, the entire screen filled with blinding dust. Then the link to the mule was gone.
Jin’s voice: “Lost mule signal.”
“You have got to be shitting me. . . .”
But then it came back.
“Wait. I’m back up.”
Morra shook his head and groaned. “Oh, man. What are we doing . . . ?” He tapped at a virtual UI and brought up a distant CCTV image of the mule as seen from the Konstantin. “Jin, I think you should return to the ship.” He rewound the video and tapped “Play.” “Nicole, watch my video layer. . . .”
Tighe and Morra watched the recording as the distant mule’s work lights momentarily became obscured by a cloud of dust as its thrusters blasted downward. By the time the craft rose above the cloud, the rake was empty.
Morra spoke over the comm link. “Nicole, the rake is useless. When we turn on the electromagnet it pulls us in, and when we pop thrusters it creates a metallic cloud that acts like a Faraday cage—and also blasts the rake clean. It needs a redesign.”
Clarke replied, “How long do you need?”
“I’ll sort that out with Ade.” Morra closed the video window. “In the meantime, we could use the Archimedes’ screw to pull up a regolith sample. That should hold enough for an assay.”
“But would the screw cut into rock?”
Adisa answered instead. “Hayabusa2 data shows rock density to be low—1.5 grams per cubic centimeter. You could crumble it in your hands.”
Morra nodded. “Right. So we drill a core sample from a boulder. Bring it back to the refinery and cook it. The sooner we get a sample, the sooner we know whether this entire expedition is possible. The clock’s ticking.”
They all glanced at the countdown, hovering at the edge of their vision.
After a few moments Clarke said, “All right. Let’s do it.”
* * *
—
Two hours later Tighe and Morra again sat at their workstations watching a shared holographic display of Mule 1 hovering above a boulder on Ryugu’s surface. Except this time the mule had a different tool attached to its lower docking port. The Archimedes’ screw consisted of a polymer tube, 20 centimeters in diameter, inside of which was an aluminum auger, the sharp point of which jutted out like a corkscrew.
The mule’s work lights illuminated a massive boulder rising tens of meters above the surrounding terrain—high enough that the surface was mostly lost in shadow.
Jin’s voice came in over the comm link. “Twenty meters.”
The ashen, irregular surface of the boulder came into view.
Clarke said, “Aim for the highest elevation, Han.”
“Maneuvering . . .”
The mule popped thrusters as Jin piloted the vehicle in, guiding the auger tip. Thrusters fired course corrections occasionally. Finally, the auger touched down with the full mass of the mule behind it, penetrating the surface.
“Activating auger . . .”
The blade bit into the ashen rock and started sinking from sight. Ryugu’s rock appeared to be as porous as anticipated.
Jin’s voice came in. “We are getting regolith in the sleeve.”
Tighe and the others applauded. He and Morra high-fived across the workstation.
The auger began to sink deeper into the rock.
Tighe watched the hologram. “Why don’t we just keep doing this?”
Morra studied the image. “Burning 20 kilos of thruster gas to get 50 kilos of regolith isn’t exactly efficient.”
They watched for another minute or so until Clarke announced, “Jin, that should be plenty. Bring the core sample back to the bottom airlock and offload it into Pressure Vessel 1. Amy?”
Tsukada’s voice came over the comm link. “Here, Nicole.”
“Work with Jin to make sure the sample gets into your refinery. Tell me when you’re ready to begin the assay. I want every step on video for mission control.”
* * *
—
By early afternoon Tighe, Abarca, and Morra sat around the galley table as Clarke arranged virtual video windows to reveal every corner of the Konstantin’s refinery.
The refinery was located in the aft section of the ship, just forward of the engine room. Surveillance cameras showed branching groups of color-coded piping and conduits running in and out of a central chamber. Neither the refinery nor the engine room of the Konstantin was pressurized, to limit the risk of fire.
Like all of the crew, Tighe had been trained to process asteroid regolith—but up until now it was theoretical, only having been done with asteroid simulant back on Earth.
Clarke spoke over the comm link. “Amy, Gabriel tells me that Nathan Joyce is watching. So I want you to bring us through each step of the refining process. Understood?”
Tsukada replied, “Understood, Nicole. Stand by.”
A virtual window expanded, providing a view into what looked like an industrial clothes dryer with metal fins set into the walls. The chamber was filled with a cloud of floating ash.
Tsukada said, “Assay 1, Ryugu, January 31, 2034, 1321 hours UTC. Initial sample mass: 87.32 kilos. Note that the regolith sample has been pulverized to increase surface area for chemical reactions.” She was silent for several moments. “Spectrometer readings confirm composition consistent with carbonaceous chondrite—which is what Catalyst mission planners were expecting.”
Tighe, Morra, and Abarca applauded.
Clarke’s voice broke in. “I’m sure they’ll be happy to hear that, Amy.”
A reddish glow appeared in the interior of the pressure vessel.
“Heating sample to 500 degrees Celsius. This will cause the hydrates to release their volatiles—that is, chemical compounds with low boiling points.”
Tighe and the others watched a mist forming amid the dust.
“What you see being released here is mostly water vapor.”
Again the crew applauded and hooted.
“However, this vapor also contains impurities—ammonia, carbon monoxide, nitrogen, methane, hydrogen cyanide, hydrogen sulfide. We’ll need to filter these out using in situ chemical oxidation—fortunately I should be able to synthesize the hydrogen peroxide and potassium permanganate necessary for that from Ryugu’s regolith.”
