Tranquility  ·  Note  ·  August 2026

How to Read Tranquility in 2026

This is an exploration. It is not a company asking you to believe a launch date. The fact that the brief changed in ten months is the useful part.

Phil Cheevers  ·  Pink House Technology

Tranquility is a constraints-first evaluation of putting AI training compute on the Moon, powered by containerized thorium reactors. It was shelved because it sounded crazy and because the hard stops were real. It is back on the desk because those stops have moved, not because someone signed a contract.

Do not take it too seriously in the way you take a prospectus. Take it seriously in the way you take a lab notebook. The point is to see whether power for compute has a future that is not “more of Earth’s grid, please.” If the answer is no, the papers should show you where it dies. If the answer is “not yet,” they should show you what changed.

What it is not

• It is not a funded program.
• It is not a SpaceX agreement.
• It is not a claim that a reactor is qualified for flight.
• It is not a cloud region for chat. Training can live with the delay. Conversation cannot. This is a foundry idea.

The 2025 pack has large numbers — gigawatts, flight counts, dollars. Treat those as tabletop scale, the size of the question, not a bid. When a later note contradicts an earlier one, believe the later note and leave the old file up. That is how you can see the work move.

What moved in about ten months

Reactors. Modular thorium and molten-salt designs kept appearing. The hardware conversation is less theoretical than it was when this was boxed. That still does not mean a unit is ready for the Moon. It means “there are no reactors” is no longer the first sentence.

Lift. The Starship-class problem did not vanish. It became a more ordinary industrial bet: if that vehicle class works, cargo math starts to close. Pink House does not build the rocket. The brief should not pretend it does.

Heat. The first cooling story was shipped aluminum. The better story is sintering — spend waste heat turning regolith into pavement, which is also how you fight dust and build a yard. That is why this is a surface program. Lagrange and free orbit still fail the heat test. They have nothing to pave.

What you mine. Thorium in the dirt is not the first mine. Water ice is, and hydrogen comes with it. Some of the mass we were going to fly does not have to be flown. The exact dollars are not closed. The sequence is: fly the fuel, sit by the ice, leave the logo in the ground.

Time and cost. Earth-side training power is still opening a gap. Cost is still a function of time and markets. Those two did not get prettier. They are why an evaluation that looked like science fiction is worth keeping in public.

How to use the library

Read the 2026 notes first if you are new. Then ask the corpus a rude question. The ask box is told not to invent a flight rate or a treaty. If a 2025 paper and a 2026 note disagree, the disagreement is the content. That is what “the whole thing has changed” looks like on paper, and it is a good thing. A brief that cannot change is a brochure.