THE RELATIVITY LAB
A journey changes your time.
Move through space. Watch two clocks tell different stories.
ROUND TRIP · EARTH REFERENCE FRAME
τ = t √(1 − v²/c²) = t / γ
EARTH CLOCK · t
YOUR CLOCK · τ
YOU AGE LESS BY · Δ
Set your journey
Illustration is not to scale: distances are logarithmically compressed and directions are schematic, not a sky map. Objects reveal as the outward distance is reached; their positions do not imply encounters along your route. Playback is an accelerated illustration, not elapsed real time.
Physics, distances & sources
Constant cruise speed in flat spacetime; instantaneous departure, turnaround, and arrival. Acceleration time, gravity, fuel, moving destinations, and cosmic expansion are excluded. Earth is the reference frame; one-way clock comparisons use Earth-frame simultaneity. c = 299,792,458 m/s is fixed. Years are Julian years (365.25 days); distances are Earth-frame light-years. Solar-system positions are an illustrative fixed configuration using rounded orbital radii, so planet distances are estimates, not current ephemerides. Star distances are rounded. The catalog is curated, not a complete inventory of the universe.
Einstein Online: traveling twins · ESA: nearby star distances · NASA: Solar system