Back to today’s briefing

Story perspectives

Sun’s Core Photons Need 100,000 Years to Reach Surface

6/18/2026

24 2 Full Breakdown

Summary

Story summary

Photons from the Sun’s core take about 100,000 years to reach the surface.
Each photon travels ~1 cm before scattering off a free electron, repeating billions of times in the inner 70 percent radiative zone.
Scattering lengthens travel to a trillion-fold versus a two-second straight path.
The sunlight we see now, whose photon was born when modern humans spread beyond Africa while Neanderthals lived, reflects last-ice-age core conditions.

1 of 1

Story summary

Photons from the Sun’s core take about 100,000 years to reach the surface.
Each photon travels ~1 cm before scattering off a free electron, repeating billions of times in the inner 70 percent radiative zone.
Scattering lengthens travel to a trillion-fold versus a two-second straight path.
The sunlight we see now, whose photon was born when modern humans spread beyond Africa while Neanderthals lived, reflects last-ice-age core conditions.