200 Science Facts

156

It can take a photon 40,000 years to travel from the core of the sun to its surface, but only 8 minutes to travel the rest of the way to Earth

- Photon travels, on average, a particular distance d before being briefly absorbed and released by an atom, which scatters it in a new random direction. From the core to the sun's surface (696,000 kilometers) where it can escape into space, a photon needs to make a huge number of drunken jumps. The calculation is a little tricky, but the conclusion is that a photon takes between many thousands and many millions of years to drunkenly wander to the surface of the Sun. In a way, the light that reaches us today is energy produced maybe millions of years ago.