384,400 km apart: the Earth and the Moon at true scale
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The Moon is 384,400 km from Earth, centre to centre[1], and in Hostile Flagship it is exactly there. The Earth, the Moon and the Sun share one frame at their true sizes: Earth 6,371 km in radius[2], the Moon 1,737.4 km[1].
One frame for everything
Everything in the game, every ship and every travel point, is placed in Earth’s own map frame, with Earth at the origin. The view turns so that the body you are near is always below you.
- Earth uses NASA’s Blue Marble maps: a day map, real cloud cover and a global height map. In game, each grey level of the height map is about 25 m of ground.
- The Moon is tidally locked, so its near side always faces Earth. In game it sits 5° off the Earth–Sun line, close to new moon.
- The Sun is fixed: a June solstice morning, overhead at 23.4° N, 90° E.
From geostationary orbit, 35,786 km up and 42,164 km from Earth’s centre[3], the whole planet fills about 17° of the sky in game.
Eleven places to stand
You don’t fly freely between Earth and the Moon. You jump between fixed points, called nodes. In game there are 11:
| Where | Nodes | Height |
|---|---|---|
| High lunar orbit | far side, east, west | 10,000 km above the Moon |
| Earth–Moon L1 | 1 | 326,400 km from Earth’s centre |
| Geostationary orbit | 100° E, 140° W, 20° W | 35,786 km |
| Low Earth orbit | over Sumatra, over Ecuador | 400 km |
| Surface zone | Bukittinggi, Bangkok | 25 km |
The links follow a simple rule: nothing jumps through Earth or the Moon. From the far side of the Moon you go round to the east or west point, then to L1, then to a geostationary slot, then down to low orbit. There is no shortcut from L1 straight to low orbit; it was tried and dropped.
Trip times in game are worked out from a 1 g burn, flipping halfway. Low orbit to Bukittinggi takes about 7 minutes. L1 to geostationary orbit takes about 3 hours.
Drawing something 384,400 km away
Godot, the engine the game uses, draws nothing further than about 10,000 km from the camera. So when a planet’s horizon is further than 4,500 km, the game draws a scaled stand-in: shrunk, and moved toward the camera by the same factor every frame. From the camera it looks identical: same size, same direction, same parallax. In low orbit the horizon is only about 2,300 km away, so there Earth is drawn at true scale. Automated tests check both the Earth and the Moon.
Where the fighting happens
Each node is a fixed circle of play: 800 km across in space (400 km radius), 200 km across in the surface zone (100 km radius). Ships stop at the edge and leave only by a travel order. Near the ground, ships fly in height bands: Top at 25 km, High at 15 km, Med at 5 km, and Low, which follows the terrain at 300 m.
The node map (F4) shows all of it flat: Earth’s surface, low orbit and geostationary rings at their real longitudes, L1 between them and the Moon. Hover over a link to see its trip time and your ships’ fuel. How that fuel is worked out is in Jump drives and fuel.
Related
- 326,400 km out: the Earth-Moon L1 point
- 36 tanks to Pluto: jump fuel from the rocket equation
- Orders, not joysticks: commanding the fleet
Sources
- Moon Fact Sheet, NASA Space Science Data Coordinated Archive.
Volumetric mean radius (km) 1737.4 … Semimajor axis (10^6 km) 0.3844
- Earth Fact Sheet, NASA Space Science Data Coordinated Archive.
Volumetric mean radius (km) 6371.000
- Geostationary orbit, Wikipedia.
a circular geosynchronous orbit 35,786 km (22,236 mi) in altitude above Earth's equator, 42,164 km (26,199 mi) in radius from Earth's center