Travel Times to Key Destinations
How long does it take to reach various cosmic destinations at different speeds? All times in Earth years unless noted.
The Speed Reference
| Label | Speed | km/s | Context |
|---|---|---|---|
| Voyager 1 | 0.000057c | 17 | Current fastest departing spacecraft |
| Fast probe | 0.01c | 2,998 | Advanced tech-ion-drive |
| Starshot | 0.2c | 59,958 | mission-breakthrough-starshot target |
| Fast ship | 0.1c | 29,979 | Plausible tech-fusion-drive |
| Relativistic | 0.5c | 149,896 | Advanced tech-antimatter-drive |
| Ultra-relativistic | 0.9c | 269,813 | Theoretical maximum for crewed flight |
Travel Time Matrix
Earth Years (as measured by observers on Earth)
| Destination | Distance | Voyager speed | 0.01c | 0.1c | 0.2c | 0.5c | 0.9c |
|---|---|---|---|---|---|---|---|
| dest-proxima-centauri | 4.24 ly | 73,000 | 424 | 42.4 | 21.2 | 8.5 | 4.7 |
| dest-alpha-centauri A/B | 4.37 ly | 75,300 | 437 | 43.7 | 21.9 | 8.7 | 4.9 |
| Barnard’s Star | 5.96 ly | 102,700 | 596 | 59.6 | 29.8 | 11.9 | 6.6 |
| Wolf 359 | 7.86 ly | 135,400 | 786 | 78.6 | 39.3 | 15.7 | 8.7 |
| Sirius | 8.60 ly | 148,100 | 860 | 86.0 | 43.0 | 17.2 | 9.6 |
| Tau Ceti | 11.9 ly | 205,000 | 1,190 | 119 | 59.5 | 23.8 | 13.2 |
| dest-trappist-1 | 39.5 ly | 680,600 | 3,950 | 395 | 197 | 79.0 | 43.9 |
| dest-sagittarius-a | 26,000 ly | 448M | 2.6M | 260,000 | 130,000 | 52,000 | 28,900 |
| dest-large-magellanic-cloud | 160,000 ly | 2.8B | 16M | 1.6M | 800,000 | 320,000 | 177,800 |
| dest-andromeda | 2.537M ly | 44B | 254M | 25.4M | 12.7M | 5.07M | 2.82M |
Ship Time (accounting for concept-time-dilation)
At high speeds, time dilation means the crew ages less than Earth observers. Ship time = Earth time x sqrt(1 - v2/c2).
| Destination | 0.5c ship time | 0.9c ship time | 0.99c ship time |
|---|---|---|---|
| dest-proxima-centauri | 7.4 years | 2.1 years | 0.67 years |
| dest-trappist-1 | 68.4 years | 19.1 years | 6.1 years |
| dest-andromeda | 4.39M years | 1.23M years | 362,000 years |
The takeaway: Time dilation helps significantly for nearby stars at extreme speeds, but cannot make intergalactic travel feasible for biological life.
Visual Scale
Proxima |----| 4.24 ly
TRAPPIST-1 |----------------------------------------| 39.5 ly
Galactic center [================================================] 26,000 ly
Andromeda [way off the chart ~~~~~~~~~~~~~~~~~~~~~~~~ ] 2,537,000 ly