Question

travelling at the speed of light how long would it take your reach the planet Neptune

Answer 1

as you reach in to the speed of light you can travel very fast and the time stops for you i dont the distance from here to neptune but you can find it by divide the total distance from here to neptune and then divide it by the speed of light that is 3000000km per second and your answer is there

Answer 2

Heya 

The Neptune is about 4.7 billion kms. away from the earth
As we know that the light travels at the speed of 299,792 kilometers per second.

so as time travelled= distance / speed
=about 250 minutes.

thus it would take about 250 minuted to reach neptune at the speed of light