BETWEEN EARTH AND MOON

Concordia.
A world in motion.

A city turns inside this vast habitat. Follow one family from a quiet morning at home, through its streets and stations, and out into cislunar space.

ANGULAR MOMENTUM BALANCED

Spin seen from the spaceport (+X) end. Shares of the four city rotors' total. turn the other way from , so the city cancels itself.

−0.0626 rad/s · 100 s/turn−50.0%

+0.0626 rad/s · 100 s/turn+50.0%

CITY NET+0.0%

(industrial)−0.044 rad/s · 143 s/turn−4.0%

Momentum ringshold it and trim cargo moves+4.0%

NET+0.000%

Turns like a ship. A small thrust starts a turn and a small thrust stops it.
No gyroscopic side-step. Push a spinning body to turn it and it swings at right angles instead.
The rings take the swings. Cargo moves shift the industrial rotor by a fraction of a percent. The rings follow, and bearing motors trade the momentum for electricity, not propellant.

If all four city rotors turned one way, a 1° a day turn of the axis would take 4.5 MN at each hull end, nonstop. Cancelled in pairs, it takes about 4 kN for a day to start and a day to stop.

CLICK SCENE TO LOOK AROUND · WASD TO WALK

✳AN ORDINARY MORNING, 2,500 METERS FROM THE AXIS

CONTROLS

Keyboard shortcuts

Move

WS or ↑↓: Forward / back
AD or ←→: Strafe left / right
Space or PgUp: Jump (walk, double-tap to take off) · up (fly, space)
C or PgDn: Down (fly, space)
V: Take off (walk) · drop and land (fly)
Shift: Hold to boost
[]: Halve / double base speed
ZX: Roll (fly, space)
H: Level to gravity or station axis
F: Transfer between frames

Rides (Explore mode)

G: Board the train standing beside you on a platform, or an ascender cabin at its deck or hub terminal (the prompt appears at the bottom left)

Glider (Explore mode, inside a city rotor)

B: Board the glider (walk or fly) · stow it (stopped on the ground)
WS: Assisted: faster / slower · manual: nose down / up · on the ground: roll
AD: Assisted: turn left / right · manual: bank · on the ground: steer
SpaceC: Assisted: climb / descend (hold C to land) · manual: throttle up / down
Shift: Wheel brake on the ground · faster changes in the air
T: Assisted or manual flight
Y: Cockpit or chase view
R: Drop the ball and see where it lands

Look

QE or ,.: Orbit left / right around the point under the cursor
HomeEnd: Orbit over / under that point
Wheel: Dolly toward the cursor target
L: Toggle mouselook (pointer lock)
Drag: Look around

Interface

M: Habitat map
3: Engineering view
N: Night at once (press again for the clock)
U: Cycle interface: full, minimal, clean
I: Show or hide the links to the guide
P: Save the frame as a PNG
`: Debug inspector: click inspects, Shift+click pins, ~ copies a bug report
Enter: Continue the story
?: This list
Esc: Leave mouselook, close a panel, restore the interface

What is real

The 21 km station is at full scale. Styled: Earth, Moon and Sun are about 650 times closer than real, at their true apparent size; the stars are random; story time is compressed; the street crowd is a sample. The full list

Report a problem

Something broken, slow or wrong? Press ` to open the debug inspector, then ~ to copy a report with your camera pose, a repro link, your GPU and recent console errors. Paste it into a new issue on the public issue tracker.

CCONCORDIA

ASSEMBLING A WORLD IN MOTION

Four rotors, each 2,500 m in radius, turn once every 100 seconds to hold a city of about a million people at 1 g.

Enter begin the story
WASD walk, drag to look
M map
? every key

Credits

Concordia.
A world in motion.

Habitat atlas

Engineering layers

Concordia

Keyboard shortcuts

Move

Rides (Explore mode)

Glider (Explore mode, inside a city rotor)

Look

Interface

What is real

Report a problem

Concordia.A world in motion.

Habitat atlas

Engineering layers

Concordia

Keyboard shortcuts

Move

Rides (Explore mode)

Glider (Explore mode, inside a city rotor)

Look

Interface

What is real

Report a problem

Concordia.
A world in motion.