Interactive
How long would it take you to get there?
Pick a destination, pick an engine. Real physics, honest estimates — from a 3-day Moon hop to an 85,000-year crawl to another star.
Want more toys? Browse all interactives — including the Mars terraformer.
Under the hood
How we calculate it
Chemical, ion, and nuclear trips inside the solar system use the Hohmann transfer — the minimum-energy path between two orbits, and the baseline real missions plan against. Ion and nuclear times are scaled from it (0.7× and 0.55×), which is an estimate: real trajectories are mission-specific.
Interstellar trips use a cruise-speed model: 15 km/s for chemical (near the fastest flown), 25–30 km/s for ion and nuclear, and 20% of light speed for the lightsail — the Breakthrough Starshot concept.
Distances use average orbital radii, and the Moon gets its Apollo-style 3-day leg. Light-time is simply distance divided by the speed of light. Nothing here is exact; everything here is honest.
Common questions
How long does it take to get to Mars?
About 6–9 months by chemical rocket on a minimum-energy Hohmann transfer — that is what real missions like Perseverance flew. A nuclear-thermal rocket could roughly halve that; a theoretical lightsail at 20% light speed would make it in under half an hour (but could never slow down).
How long would it take to reach Proxima Centauri, the nearest star?
About 21 years by lightsail at 20% the speed of light — the Breakthrough Starshot concept. By chemical rocket at the fastest speeds ever flown, the same trip would take roughly 85,000 years: longer than our species has existed.
Why do travel times vary so much between propulsion types?
Chemical rockets are limited by the energy in their fuel; most of the spacecraft ends up being propellant. Ion drives are far more efficient but produce gentle thrust over months. Nuclear thermal roughly doubles chemical performance. Lightsails need no onboard fuel at all — a giant laser pushes them — which is why they can approach a fraction of light speed.
Are these numbers exact?
No — they are honest estimates. Solar-system times use Hohmann minimum-energy transfers between average orbital distances; real missions optimize for launch windows, gravity assists, and arrival speed. Interstellar times use a simple cruise-speed model. The physics direction is right; the decimals are not the point.