27 January 2017

Incredible fact


This is hard to comprehend:
"It takes a million years for a photon moving at the speed of light to reach the sun's surface from its core."
Explained on the basis of Thomson scattering: "The mean free path of a photon in the interior of the sun is about 2 centimeters. This is the average distance it travels in between bounces. If you compare this length to the radius of the sun, you see why it takes so long for the photons to escape."

Additional discussion and clarification of the "bouncing" in this thread.

2 comments:

  1. JeffJanuary 27, 2017 at 12:58 PM

    Not to mention, the cumulative radiation pressure from all those photon collisions help support stars' interiors from the crush of gravity.

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  2. Stan B.January 27, 2017 at 9:41 PM

    And when you take an analog photo (ie- use film) the photons bouncing off your subject are embedded unto the film.

    ReplyDelete