3
Expedition
Will Elliott had relatively little time to get angry at Sebastian and Roger. Roger agreed to a three-day expedition southward to the chaotic terrains, which Will was happy to lead. When they returned, the first automated cargo vehicle had aerobraked into Mars orbit and the Olympus, crewed by Sebastian and Paul, was ready for launch to retrieve the contents. After the shuttle blasted off, the two rangers towing portahabs headed eastward for another three-day expedition to the mouth of Gangis Chasma, and they actually pushed farther eastward along the northern escarpment of Aurorae for an additional thirty kilometers.
They returned just before the Olympus landed. It brought fifteen tonnes of new cargo: metal working equipment, additional plastic and chemical making equipment, six Prospector-200s (200-kilogram robotic rovers), a wind turbine, and spare parts. It also brought their first conestoga, a special eight-wheeled, six-tonne vehicle similar to a terrestrial mobile home, much larger than the ranger and portahab combination—8 meters long, 2.4 meters wide, and 2.4 meters high. Unlike their portahabs, the conestoga had a built-in driving cab, with an airtight hatch between it and the rest of the vehicle so that it could serve as an airlock. Two loft sleeping cubicles over it opened on the conestoga’s main cabin, which had a “dinette” area (table and seating for four), a couch, and a galley with a three-burner stove, oven, microwave, two-basic sink, and fridge. Behind it was a hygiene area with a shower stall and a cubicle with a toilet and sink. The rear 2.5 meters of the vehicle was a scientific lab with loft sleepers for two and an exit hatch; the room also served as a pressure suit donning area and airlock. Normally accommodating four comfortably, it could support eight in an emergency. Thoroughly tested on the moon, the conestoga was an exciting addition to their exploration capacity. An even larger vehicle, the Mobilhab, which had a second story, was slated to be deployed on the moon in a matter of months and would come to Mars in two or four years.
As exciting as it was, the conestoga was immensely complicated to set up. It was an inflatable vehicle with a telescoped chassis so that it could fit in standard six-meter cargo bays. Even rolling it out of the cargo bay was complicated because the tires proved unexpectedly locked. Inflating the vehicle expanded it easily to its full size, but bolting the extended chassis together was complicated; for a long time they couldn’t get the parts to fit. The interior was filled with cargo and required extensive installation of cabinets, furniture, and loft sleepers.
The conestoga also came with an experimental automated docking system for surface vehicles. The flexible plastic tunnel that connected two hatches up to a meter apart came with a dozen inflatable ribs; differential inflation of them could steer the docking collar right or left, up or down, and in or out. The driver could use cameras to align the collar precisely and extend it into the docking receptor of the other hatch, then lock it in place. The seal was never perfectly airtight; the tunnel would deflate in an hour or so. But in practice that was sufficient for transfer of personnel between vehicles without pressure suits, since the hatches were kept closed.
While they worked on the conestoga, the Apollonaris, with Carmen and Érico on board, blasted off to pick up the cargo of the second automated cargo vehicle. Carmen and Érico had trouble transferring the cargo to the hold of the Apollonaris, even with the remote-controled arm on the Interplanetary Transit Vehicle or ITV still in orbit, and needed an extra day to do it. They also transferred methane and oxygen to the automated cargo vehicle—which had an empty mass of only two tonnes—so that it could fly back to Earth for reuse. Then they landed at the Outpost.
Another four days were consumed with unloading the Sunwing, the glass making equipment, the construction equipment, a docking unit, tunnels and connectors, a greenhouse, scientific instruments, and spare parts. The conestoga, finally set up, was taken out for a test drive. The manufacturing equipment deorbited by the two shuttles was set up at the northern end of the Outpost, bring it into its final configuration for Columbus 2. Anchoring the southern end of the outpost was Habitat 1, with Habitat 2 north of it. They were connected together by greenhouses 1 and 2 on the eastern and western sides of the habitats respectively. Extending northward from Habitat 2 were Greenhouses 3 and 4 on the eastern and western sides, respectively, and they connected Habitat 2 to Habitat 3. Extending northward on the east side of Habitat 3 was the industrial facility: two docking units, each three meters across, each with two “doors” to which a chemical, plastic, or metal processing unit could be docked. At its northern end, the Mars Life Science Facility ran due west, and at its western end was a simple plastic tunnel that ran southward to the western side of Habitat 3.
When they had all the modules connected and set up, the eleven of them couldn’t help parading from one end to the other. The Outpost now consisted of three habitats, four greenhouses, a life science facility, an industrial facility, and two pressure suit donning and cleaning facilities. It was seventy-five meters long and sixteen wide, big enough to allow a lot of walking around, with plenty of spots for solitude. A pattern was set that could be expanded almost infinitely; a Habitat could be added to the Outpost in many places, connected to the other modules via at least two escape routes to provide safe evacuation.
They still had weeks of work to set everything up, but the work would not require eleven people. That night Sebastian gathered everyone after dinner. “It’s now May 28,” he said. “On Earth, the spring semester is ending. That means every planetary geologist and exobiologist who can is heading for Houston, Paris, Moscow, Brasilia, or Tokyo. Industrial engineers, horticulturists, and space medical researchers are on their way, also. Are we ready for them?”
“The
greenhouses are in good shape and are ready for experiments,” replied Madhu.
“Thanks to Shinji and Ethel, when we arrived there was enough extra soil in
preparation that we were able to set up Greenhouse 3 almost immediately.
Greenhouse 4 will be ready by the end of the summer. So the greenhouses are
ready for various experiments that originally were scheduled for the fall. I’ve
got a team of twenty scientists ready to follow growth experiments with ten
different plant species, and we have growth experiments involving the tilapia
and rabbits.”
“How are the tilapia, anyway?” asked Ethel.
“They’re recovered pretty well from the cramped environment and
artificial gravity of the ITV and they’re now growing pretty well.”
“Ethel and I are going to be extremely busy and will need help,” said
Paul. “Both Sunwings will be deployed right away to scout out possible
exploratory routes and we have to put together Sunwing 3 as soon as possible so
we can test it. The hanger has to be enlarged to accommodate a third one. All
that work requires a lot of metal and plastic parts and filling more sandbags
to build up the hanger’s walls. The industrial engineers will all want to see
the new equipment tested. Sebastian, we’ll need your help when you’re here. We
really will need three people full time.”
Sebastian nodded. “I was assuming we’d assign you three whenever we
can, but you’ll also have to handle a lot of routine maintenance. Because the
ideal arrangement is to send out six people in all three vehicles; certainly we
need to send at least five. And that raises the question, where will we go?”
There was silence while Roger looked at Will and Will looked back at
Roger. Finally Will said, “Roger wants to head north and most of the scientists
in mission control want an exploration in that direction as well, so I will
drop my objection to it.”
Roger beamed; he was happy, not relieved. Will raised a finger. “But
there is a caveat. I think we need to consider new exploration strategies that
can cover more ground. If we adopt them, a northward expedition is possible
with enough time left for a southward or eastward expedition. That’s what I
want to propose.”
“What strategies do you have in mind?” asked Roger uncomfortably.
“We tried the month-long expedition on Columbus 1 and it worked well.
But it’s really a modification of the two-week expedition strategy developed on
the moon, based on the length of the lunar day. The rangers and portahabs have
proved immensely reliable in the Martian environment. In the month-long trips
we had to shut down one fuel cell out of six on one ranger and once we had to
shut down one motor out of six. If we send six people along we’ll have more robust
repair capability. There’s no reason why expeditions can’t go out for two or
three months.”
“How about limitations of fuel and supplies?” asked Roger.
Will shook his head. “We’ve got new capabilities that can overcome
those limitations. We tried water extraction tents on the expeditions and they
worked in a limited way, but the new water extraction equipment is supposed to
be much better. But even if they don’t work well enough, we now have three
Sunwings that can airdrop 250 kilogram blocks of ice and food. We can use
plastic packing materials to protect them from the impact. The new water
extraction tent comes with a new regolith oxygen extractor and if it works as
expected we may be able to extract the oxygen for breathing and burning methane
as we go. And our energy situation will be very different if we send a solar
power unit along. The new ones can be set up more quickly and even if they are
less efficient at higher latitudes, they’ll still make between 1,200 and 1,800
kilowatt hours every sol.”
“Is that enough for an expedition?” asked Madhu.
“More or less. A portahab needs one hundred kilowatt-hours per sol for
their life support systems. I’d send one. A ranger needs fifty kilowatt-hours
per hour for its engine while bulldozing and twenty kilowatt-hours when just
driving. If it’s operated for eight hours bulldozing and four hours driving,
each ranger needs about five hundred kilowatt-hours per sol. I’d send two; one
to pull a portahab and one to pull a supply trailer. A conestoga needs five hundred
kilowatt-hours for driving eleven hours plus life support. The total’s sixteen
hundred kilowatt-hours per sol. The Prospectors need ten kilowatt-hours per
day. The trailer will carry the solar power unit, spare methane and oxygen,
water and supplies, and three Prospectors. The Outpost will have four buggies
and a portahab for local expeditions.”
“How would we use three vehicles?” asked Roger. “And you operated the
rangers only five hours a sol on Columbus 1; why are you suggesting seven hours
now?”
“On Columbus 1, whenever the expedition involved extravehicular
activity, route-clearing had to stop. Both rangers sat while two or more of us
walked around and explored. But with three vehicles, the conestoga can stop
with the explorers—two people outside, one in the conestoga to provide
emergency backup and run the Prospectors—while one ranger pushes the trail
forward and the other follows with the portahab and trailer and cleans up the
trail. When the explorers finish, they can jump into the conestoga and catch
up. I’d divide the day into three activity periods of three and a half hours
each. Each crew would spend two activity periods bulldozing the route and the
third stopping for exploration or doing chores. The result will be a higher
quality trail—probably one rated for forty kilometers per hour—and thirty
kilometers of new trail per sol. Assuming six sols of exploration a week,
that’s 180 kilometers per week. The 4,000 kilometers to the northern layered
terrain can be accomplished in twenty-two weeks; less than half a year.”
“You’re calling on people to work ten and a half hours a day, though,”
said Sebastian.
Will shook his head. “Not necessarily. Driving will require seven hours
times three drivers or twenty-one hours. If we have two pairs of people outside
for three and half hours each, that’s fourteen hours more. That’s a total of
thirty-five hours; divided among six people, that’s about six hours each. Food
preparation, sample logging, reports about each stop, etc., can be accomplished
in two or three hours a day times six people.”
“And where will the solar power unit be, all this time?” asked Roger,
skeptically.
“At a home base. You set it up, leave it, and let it make oxygen and
methane for a week. You also set up the extraction tent and let it heat and
repeatedly wet the regolith in order to extract water and oxygen from it. Then
you send one ranger back with the trailer and portahab. It travels the 180
kilometers of new route in five or six hours and packs up the home base. The
next morning it drives back to the other vehicles and they set up a new home
base.”
“That should work,” said Érico, impressed.
“It’s a plan cobbled together from various proposals,” snorted Roger.
“It’s true, the elements are published in different places,” replied
Will. “But I’m not proposing that we try it all from the beginning. Nor am I
proposing we run all of this past mission control. Instead, I am proposing that
we try different pieces of the plan at different times; we experiment and
gradually develop a plan suited best to our resources.”
“Are you assuming that once the mission sets out, it doesn’t return
until it reaches its destination?” asked Ethel. “Because it could be quite a
hardship living in a portahab and a conestoga for six months, even with the
bigger space the latter provides.”
“No,” replied Will. “I am assuming we will use the Sunwings. When the
expedition reaches the first fifteen hundred kilometer mark, about eight weeks
after it starts, Sunwings will fly down a half tonne of solar panels, a water
tank, a methane tank, an oxygen tank, a small fuel cell and Sabatier reactor,
and a few other basics. It’ll take four flights. The crew will set up an oasis.
That way when the expedition has to drive back to the Outpost, it can refuel
every fifteen hundred kilometers. It would take a vehicle three sols, driving
at forty kilometers per hour during daytime, to reach the Outpost. So two
vehicles could return for rotation purposes, then turn around and drive back
about ten days later, refueling as they went. But it would be even faster and
easier to get the Sunwings rated for human use. A Sunwing could fly two people
fifteen hundred kilometers in about ten hours.”
“It’d be a long relief flight from the northern layered terrain!”
exclaimed Roger.
“Faster than on the ground. A four-thousand kilometer flight would take
almost twenty hours. They could always land halfway in between at an oasis and
walk around for a few hours. The Sunwing’s cabin is big enough for standing and
for sleeping, so it wouldn’t be too bad.”
Sebastian looked at Will respectfully. “This is a very intriguing idea.
As you say, the elements are all published. But no one has put them all
together.”
“That’s because no one has dared. They aren’t here; they’re not sure
what’s really feasible. The only way to find out is to try the different
elements. The real key is the Sunwings. Now that we have three of them and two
of them have flown flawlessly for two years, we know we can rely on them. The
Sunwings actually could provide the expedition with all the methane and oxygen
it needs; the expedition would need four flights a week. The solar power unit
is a much better option, though, and a flight every week or two to ship fresh
vegetables to the expedition and haul samples back to the Outpost for
preliminary analysis is a better use of the Sunwings.”
“Sunwings 1 and 2 still need a lot of maintenance,” reminded Ethel.
“Both of them have two nonfunctioning motors, and two other motors on one
sunwing and three on the other are partially nonfunctional. But we now have the
spare parts to fix them.”
“And Sunwing 3 has the new high-efficiency solar panels and therefore
has thirty percent more power,” added Paul. “It can haul more cargo, and at a
higher speed.”
“We’ll have three functioning Sunwings in another month or so,” agreed
Sebastian. “Even if the expedition sets out tomorrow, it won’t need a Sunwing
flight for a few weeks.” He looked at Roger. “So, what do you think?”
Roger hesitated. He looked at Will. “We should try some of the ideas
one at a time. I’d send out the conestoga, two rangers, a portahab, and a
trailer with the solar power unit, just as Will suggests. We can try the new
water and oxygen extraction equipment as we go. The crew rotation ideas should
be tried, too.”
“What I ask, remember, is that if these strategies work, we devote some
time to exploring either eastward or southward,” reminded Will. “Columbus 2
shouldn’t just be about exploring lowlands and searching for fossils and maybe
current life there. It also has to explore the canyonlands more or explore the
southern highlands. If we can, we should try to reach some volcanics as well.”
Roger laughed. “So, you want to drive up to Tharsis?”
“Keep in mind that Columbus 3 might,” persisted Will. “And we can make
it easier for them. We have to think long term.”
Roger looked down, irritated by Will’s lecturing.
“Okay, I get the picture,” said Sebastian. “I agree, Moonman; if the
northern expedition reaches its goals, we’ve got to go either southward or
westward. The geologists will be chomping at the bit for an expedition in about
three sols, so let’s focus on preparing for a trip northward down Simud Vallis
to Chryse. The route needs to be reviewed; there may be new data requiring
changes in the route or the proposed stops. The rangers need routine maintenance,
the conestoga needs breaking in, and there’s a lot of packing to do. We need to
decide who’s going and when we’ll rotate whom back here. I’ll get the
geologists in Houston started on the route review and will put together the
crew manifest and rotation schedule. Ethel and I can work on rangers 1 and 2.
Paul, can you set up the rovers with the solar power unit and supplies? Roger
and Will, can you work on the supply manifests?”
Everyone nodded. Sebastian smiled a slight, wan smile. “Great. We have a plan.”
The meeting began to break up. It was now 7:30 p.m.; getting late. Will and Ethel headed for their room to watch a bit of television and relax before going to bed. They walked to Habitat 1 through the greenhouses, which were now enclosed in thermal blankets and were getting chilly anyway. They didn’t speak until they reached their room.
“Did you notice that Sebastian asked the men whether they could do certain tasks, but told me what to do?” she said.
Will was startled by her comment. He thought for a second. “Oh, you’re right. Sebastian doesn’t strike me as someone enlightened about the role of women.”
“I’m afraid not.” She looked at him skeptically. “How long do you think you’ll be away?”
“I don’t know. If the Sunwing’s working, maybe I can get back for a week every month. More likely, I’ll be out two months, back two months, then out two months. We’re not talking about four month rotations, like in earth orbit, or six month rotations, like on the moon.”
“That’s true. And I could go along on one of the two trips, too.”
“We could have our own ranger.”
“That might be interesting,” Ethel considered. “I would enjoy more exploration. There are always interesting repair challenges.”
“Good scenery, too.”
“Yes, though northern Chryse gets pretty flat and boring.” She shrugged. “I guess that’s the best we can do.”