From 1veritasium, 2veritasium, or sciencium.

The outer layer of the sun is slowing down, something we’ve known for decades but haven’t been able to figure out until now.
Supported by Google Making & Science: http://youtube.com/makingscience

References:
A Poynting-Robertson-like drag at the Sun’s surface
Ian Cunnyngham, Marcelo Emilio, Jeff Kuhn, Isabelle Scholl, Rock Bush
https://arxiv.org/ftp/arxiv/papers/1612/1612.00873.pdf

https://en.wikipedia.org/wiki/Poynting–Robertson_effect

Edited and Animated by Jesse Agar
Music from http://epidemicsound.com "Serene Story 2"