What do you think of this fact?
When the Sun shines on your face, that light has only been traveling for a few minutes. The story behind it is a lot older, though.
The fast part of the trip
Earth is on average about 150 million kilometers from the Sun. Light covers roughly 300,000 kilometers per second. According to BBC Sky at Night Magazine, that works out to a travel time of about 8 minutes and 20 seconds. Because Earth’s orbit is slightly oval, it ranges from about 8 minutes 10 seconds to 8 minutes 27 seconds.
Which also means: if the Sun suddenly vanished, you wouldn’t notice for a good 8 minutes.
The traffic jam inside
The long part comes before that. The Sun’s energy is produced deep in its core through nuclear fusion. The distance from there to the surface is much shorter than the distance to Earth, but the route is completely jammed. The Sun’s interior is so dense that light can’t just zip through.
According to NASA, a particle of light on its way out is absorbed by atoms and re-emitted again and again, each time in a random direction. NASA calls it a “drunken walk.” Instead of a straight line, it zigzags back and forth. NASA says this journey takes tens of thousands of years and gives a figure of about 40,000 years. BBC Sky at Night Magazine speaks of thousands or even tens of thousands of years. So the exact estimates differ, but it’s millennia either way.
Strictly speaking, it isn’t the same particle that arrives, but the energy that keeps getting passed along. The result is still absurd: the warmth on your skin started working its way out of the Sun thousands of years ago.
Bonus fact: According to NASA, once light leaves the Sun it travels about 93 million miles to Earth, which is roughly 150 million kilometers.
Eight minutes of sprinting after millennia in traffic. Sounds like rush hour.