At the speed of light to the Andromeda Galaxy: about 2.5 million years
At the speed of light (1,079,252,849 km/h) it would take about 2.5 million years to get to the Andromeda Galaxy – at a distance of 2.37 × 10¹⁹ km, non-stop and in a straight line.
For comparison
The light you see from Andromeda today set off before Homo sapiens existed – when the earliest humans of the genus Homo were just appearing.
How it is calculated
- Distance
- 2.37 × 10¹⁹ km (2.5M ly)
- Speed
- 1,079,252,849 km/h
- Formula
- Travel time = distance ÷ speed
- Result
- 2.37 × 10¹⁹ km ÷ 1,079,252,849 km/h ≈ 2.5 million 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: Andromeda Galaxy
The Andromeda Galaxy is the nearest large spiral galaxy and, at about 2.5 million light-years, one of the most distant objects you can see with the naked eye under a dark sky. It contains roughly a trillion stars and is larger than our Milky Way.