Satellite builder

Pick a destination, pick a bus, load it with instruments. The budgets update as you go, and the build is judged against the real physics of where it is headed: sunlight thins with distance, Jupiter's radiation eats electronics, and the deep dark needs nuclear power.

1 · Choose a bus

2 · Load instruments

3 · Choose the engine

The cruise engine and its propellant load must buy the speed change this destination demands: braking into orbit, plus a margin, plus years of station-keeping. The full engine hall lives on the rides page.

4 · The verdicts