01 · Source: start from measurement
A campaign starts with the best public data for its destination. For the Moon that is laser altimetry from NASA’s Lunar Reconnaissance Orbiter (LOLA), at 5 m per pixel near the south pole, and colour imagery from its wide-angle camera. For Mars it is MOLA elevation and orbital imagery; for Ceres, the Dawn mission’s global mosaics; for Europa, the Voyager and Galileo maps that Europa Clipper will soon replace.
Positions in the sky come from planetary ephemerides published by NASA’s Jet Propulsion Laboratory, so the Sun, Earth and the planets are where they really are on a given date. Physical constants come from NASA fact sheets and peer-reviewed papers. Each source is listed on the data sources page.
We use what is public. When the best available data are coarse, we use them anyway and say so.
02 · Constrain: turn physics into rules
Data become rules. Sunlight and shadow are computed from the terrain and the Sun’s position, hour by hour. Line of sight to Earth decides when a base can talk home. Slope decides where a rover can drive. Radiation dose accumulates with exposure and shielding. Transfer windows and Δv (the change in velocity a trajectory needs) decide when cargo can arrive and how much it costs.
The rules are deliberately simple where simple is enough, and every simplification is written down. A rule that cannot be traced to a source or a stated assumption does not go in.
03 · Play: let people decide
Then the player decides: where to put the base, how to power it, what to ship and when. The campaign scores those decisions against the rules: hours of power, days without contact, dose received, mass delivered. A good score means a plan that would work, not one that looks good.
Every number on screen can be traced back to its source.
Four principles
P1 · Every number has a source. If we can’t cite it, it doesn’t drive the simulation. When we compute a value, for example a signal delay from a distance and the speed of light, we say so.
P2 · Show the uncertainty. Coarse data and simplified models are labelled on screen. When a figure is disputed, as the thickness of Europa’s ice shell is, we give the range and both sources.
P3 · Rules come from physics. Scores reward what would work. Nothing is tuned to make a dramatic outcome more likely.
P4 · Play to understand. The game makes trade-offs tangible: power against distance to water, shielding against mass, speed against propellant. It never bends the science to make the game easier.
What we do not claim
A campaign is a model, not a mission design. It does not replace engineering analysis, and its 3D scenes are not to scale where scale would hide the destination. On the home page, distances and sizes are compressed so every world fits in one flight.