Hard Tech & Science — Ten Kilometers an Hour
Hard Tech & Science – Ten Kilometers an Hour
Moon Dispatch
On the South Road the crawler is an all-terrain vehicle at ten kilometers an hour or less. At twenty, Nils tells Doc, a rock he cannot dodge will wreck it.
Moon base hard science fiction: air, water, power, and the narrow buffers that keep the Habs alive.
A pressurized crawler on the South Road is not a truck. The sealed mass transports air, water, battery, and two people across unprepared regolith, and they cannot walk home if the hull breaches. The recommended speed is ten kilometers an hour or less. At twenty, a rock Nils cannot dodge will wreck it. That is the constraint. Mass, dust, and that the surface does not get smoother the further south you go.
The Constraint
Ten kilometers an hour is about six miles an hour. It feels slow because Earth habits are wrong for the ground. On Earth, drivers expect an all-terrain vehicle to absorb a rock, or they expect to spot it in time and steer around it and at the very least be able to call someone if it goes wrong. On the Moon, the crawler has mass and inertia, though it has less weight. One-sixth g does not make a sealed pressure vessel nimble. If the suspension has any significance, the builders did not design it to withstand a twenty-kilometer-an-hour collision with a boulder the size of a man’s torso. Nils says it plain while he is already going faster than he has gone before. They are ATVs at ten or less. At twenty, he can wreck in nothing flat.
The South Road gets worse with distance. As the crawler moves further south at the recommended speed, the driver can steer around the rocks he sees, or the slow impact prevents anything from breaking. At twenty, the reaction distance shrinks, and the energy goes up. A rock he would have threaded at ten becomes a potentially hull-breaching event. Earth training says hurry. The ground says that the hurry is how you stop moving.
How It Works at Conrad
The architecture is a pressurized crawler on tracks already cut into the regolith. Solar-plus-battery for the drive. Oxygen and the recyclers inside the cabin. Seals at every hatch. Dust that works into anything that moves. The South Road is one of the named tracks between the station and the habitats further out. It is not a graded road. It is a path that gets rockier as it leaves the worked ground around Conrad.
Nils is driving. Doc Keller is in the passenger seat. They are going after Tilly, who has already taken the sleeping pill and is no longer answering. Nils tells her at least another twenty minutes. He is taking it faster than he has done before, and he tells her why that is a problem. More rocks. They will have to slow way down. Doc wants him to hurry, anyway. Apart from killing us, can you hurry? He can. That is the whole negotiation. The crawler will do the speed. The surface will decide whether the crawler is still a crawler when they arrive.
Later, on other runs, the auto-drive will hold a pre-set twenty-five. That number is already above the wreck threshold Nils named on the South Road. The system assumes that the tracks are clear enough, or that the driver will take it back. Neither assumption is free.
What Fails First
What fails first is something Nils does not name precisely because he does not have to. A rock. At twenty. The hull, a wheel, a seal, a drive unit — any of them ends the trip. Who notices is the driver if he is still watching the ground instead of the clock. Doc notices the time. Tilly is the reason the speed is already wrong. The three-day lag means a wrecked crawler is not a tow. It is a recovery that Earth cannot stage before the air in the cabin, or the air in the habitat they were trying to reach, has already decided the outcome.
Nils is racing because a woman on the surface has a radiation problem, and the cellar is behind them. The crawler does not care why. At ten, it is an all-terrain vehicle. At twenty, it is a mass that will meet a rock it cannot dodge. Faster is still how you break it.
If the South Road only stays a road at ten kilometers an hour, what are you actually driving when the reason to hurry is already in the next habitat?
Further Reading
- The Lunadyne Incident and Other Stories — “CME”
- Thunder Moon Tussle
- Mask of the Joyful Moon
- Related site posts: Hard Tech & Science — Storm Cellar, Hard Tech & Science — Eight Minutes, Frontier Foundations — Gordonville, Life on the Frontier — When the Alarm Sounds
The Joyful Moon is still watching…
and faster is still how you break the crawler.
— Torn MacAlester
Still riding the trails with Nils, Gen, and the whole Fabulae Lunae crew
🚀🌕
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StoriesThe stories of Torn MacAlester are science fiction, where the science is well-grounded. I intentionally made any deviations for speculative purposes. To maintain maximum realism, I restrict the scope of these deviations. |
ArticlesI write articles of science fact and science fiction. The articles here span the knowledge of modern science and the speculations of fiction. I try to caveat everything that is an assumption. You will find articles about spaceflight, the possibilities of alien contact, and descriptions of technology used in my stories. |
