How long does it take to travel to the nearest star at the speed of light?
The nearest star (apart from the Sun) is currently Proxima Centauri, which is about
That means that the light we currently see from Proxima Centauri started its journey about
If an astronaut were able to travel close to the speed of light, then from the perspective of observers at home, the journey would take at least
Note however, that the astronaut would experience somewhat less time, depending on how close to the speed of light they were travelling.