By plane to Neptune: about 570 years

By plane (900 km/h) it would take about 570 years to get to Neptune – at the average distance of 4.5 billion km, non-stop and in a straight line.

Because the distance keeps changing, the travel time ranges from 550 years (closest) to 590 years (farthest).

For comparison

Had you taken off around 1455, when Gutenberg was printing his Bible, you would just be landing now.

How it is calculated

Closest distance
4.3 billion km
Average distance
4.5 billion km
Farthest distance
4.69 billion km
Speed
900 km/h
Formula
Travel time = distance ÷ speed
Result
4.5 billion km ÷ 900 km/h ≈ 570 years

Assumption: constant speed in a straight line, with no stops, acceleration or braking. Real spacecraft fly curved paths and use the gravity of planets.

Good to know: Neptune

Neptune is the outermost planet and in 1846 became the first planet found by calculation rather than by observation. It is about 30 times as far from the Sun as Earth and needs 165 years for one orbit. Only one spacecraft has ever visited it: Voyager 2 in 1989.

→ Fact sheet: Neptune

Neptune: travel time by every vehicle

VehicleSpeedTravel timeRange
Car100 km/h5,100 years4,900 years – 5,400 years
Airplane900 km/h570 years550 years – 590 years
Rocket61,000 km/h8.4 years8 years – 8.8 years
Speed of light1,079,252,849 km/h4.2 hours4 hours – 4.3 hours

By plane to other destinations

▶ Space calculator