As far as we know, light is the fastest thing in the universe. From the second it is emitted from the sun, it zips off across the galaxy at an incredible 186,000 miles per second. But even though light is as fast as space-time gets, it’s slow as a turtle compared to the epic scale of the cosmos. It turns out that when you’re talking about a universe that is 76 sextillion miles wide, 186,000 miles per second isn’t very fast at all.
A great video by Alphonse Swinehart puts the speed of light in perspective, showing the over-the-shoulder view of a single proton as it zooms away from the sun.
“I’ve taken liberties with certain things like the alignment of planets and asteroids, as well as ignoring the laws of relativity concerning what a photon actually “sees” or how time is experienced at the speed of light, but overall I’ve kept the size and distances of all the objects as accurate as possible,” write Swinehart.
The video lasts 45 minutes in total, and after all that time, it ends as the particle of light passes Jupiter. According to Swinehart, Jupiter is the ending point because he wanted the video to be under an hour long. If he’d continued it, the animation would take 79.3 minutes to reach Uranus, and over two and a half hours to reach Neptune.
But if you think about it, it’s still unbelievably fast! If you could fly across the solar system at light speed, that’s only just enough time to finish the in-flight movie. But after it leaves the solar system, the nearest star is another light year away, spent hurtling through the void with nothing at all to see. When you put it that way, light may be the fastest thing in the universe, but it’s still not fast enough for our imaginations.