Hard Tech & Science – Eight Minutes
A CME alarm, a cellar under Hab D, and the water stacked over your head while 100 MeV protons arrive.
Moon base hard science fiction: air, water, power, and the narrow buffers that keep the habitats alive.
The speed of light will get you a warning. It will not get you shelter. When a coronal mass ejection leaves the Sun, Conrad Station has on the order of eight minutes before the most energetic particles arrive. Radiation is a spacer’s worst enemy. A CME is the worst of that.
In CME, the alarm hits Alex’s Bar in the middle of a tab Nils is trying to settle. Sheriff Anderson does not give a speech. He gives a location and a clock: Hab D, the cellar, eight minutes, or your insides turn to jelly.
The Constraint
There is no magnetosphere worth the name and no thick atmosphere to stop a proton. At a hundred MeV, a proton is moving at about forty percent of the speed of light. It does not dump its energy in a neat skin burn. It drives a line through tissue, knocking electrons loose, ionizing as it goes — cell wall, DNA, the slow cancers Doc Keller is already thinking about while the particles are still arriving.
Numbers from the cellar: over four thousand 100 MeV protons per square centimeter per second, and rising. Doc’s verdict, once the detector climbs, is not diplomatic. If someone is not in a shelter, they are dead.
Earth habits get people killed here. Stopping for a bag. Assuming the warning reached everyone. Assuming “outside the net” still means you have time. Tilly Masters was southwest after a KREEP outcrop, out of Conrad’s tower, and did not get the alert. She saw the rad sensors go wrong and ran for crater shade. Twenty minutes. Far too long.
How It Works at Conrad
The original station piled lunar regolith up the sides of Hab D until it was effectively underground. Most of the station’s water sat in the room above the cellar. Water and ceiling foam between the Sun and the people. McPherson dogs the upper hatch, straps foam blocks over it, and the clock becomes wait.
That architecture was never a polar storm cellar by design. Builders constructed the habitats for space, where radiation can come from any side. On the Moon, the CME is directional. Shielding under the floor does almost nothing against particles coming from the Sun. It may help with crustal background. It will not help today. Nils pulls up the grate and foam because the mass is in the wrong place, and because they need enough extra shielding in a crawler to take Doc out to Tilly without frying on the South Road.
A crater wall works the same way, if you can get behind it: rock between you and the source. Nils has ridden one out that way. He has also sat under his own hab’s regolith. None of it is perfect. All of it is geometry. Put mass between the particle and the body. Do it in eight minutes, or do not be on the surface.
What Fails First
The warning net fails first. Then the assumption that thirty people in the area means thirty people in the cellar. They are missing five. Milt Johnson is in London. Vargas and Richards check in. Tilly does not. Lunadyne’s Earth-side offices are late on the east coast. Nils does not wait. He has Milt warm a GNR antenna in Alaska and retransmits through four hundred thousand kilometers to a woman behind a mountain.
Communications can still be almost real-time. Physical help cannot. There is no Earth hospital in the eight minutes, and there is none in the three days after. Doc goes because Rule One of the prospector codes is Survive — not as a slogan, as an agreement not to let each other die if you can help it. The crawler is faster than it should be on a road that gets rockier the farther south it runs. The medical problem waiting at the far end is not a reactor leak. It is a particle that burns through living cells, and the nearest advanced center is still a three-day lag away.
The margin is the cellar, the water, the foam, and whoever is still counting heads when the detector climbs. Eight minutes is not a metaphor. It is the length of the decision.
Further Reading
- The Lunadyne Incident and Other Stories — “CME”
- Thunder Moon Tussle
- Mask of the Joyful Moon
- Related site posts: Character Spotlight – Doc Keller, The Three-Day Lag, Hab D, Life Support Margins, Nils Carmike (Revisited)
The Joyful Moon is still watching…
and the margins still have to hold.
— 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. |





