Relativistic Starfield Simulator

Click the viewport to focus, then use keyboard controls to fly.

Start the relativistic clocks manually or on next velocity change.

Live readout from the simulation frame.

Clocks and distances from spacecraft perspective.

Lorentz factor and Doppler at current β.

Type to filter. Click to select / deselect.

Stars are distributed uniformly in a spherical bubble and recycled as you travel. Lorentz aberration bunches them toward your heading at high β. Doppler shift blueshifts forward stars and redshifts rearward ones. The aberration ring shows where a cone at the chosen angle maps to after aberration.

Tip: set World speed scale to 100 and tap W several times to reach ~0.9c and watch the starfield compress forward.