(published on 12/18/2009)
Hi Bradley,
The ultimate fate of all photons is death by absorption. In which case its energy is given up to that object which absorbed it. For example photons from the sun that strike the earth are absorbed and warm it. If a photon strikes a mirror or some thing similar it can be reflected with minimal energy loss. Now some photons are as old as Methuselah and seem to last forever like the remnant photons coming out of the Big Bang. However, like Methuselah, they do age. They start out nice and blue and energetic but wind up as red or even infrared or microwave in their old age, as observed by us, due to the red-shift caused by the expanding universe.
LeeH
(published on 09/26/2014)