While watching the rebooted Cosmos series, I heard Tyson say that a photon arriving to the Earth from the Sun might be millions of years old.
If I understood correctly, once it's emitted inside the Sun's core, the chance of it reaching the surface of the Sun is rather small because it's constantly being absorbed and emitted inside the Sun.
But isn't the correct way to say that the lifetime of a photon lasts from its emission to its absorption by the encountered atom? If this atom now emits a new photon, shouldn't we regard this simply as a new photon?
Or is that single exact photon really "wandering" around and being unable to get to the surface, without being absorbed at all?