Is the Atmosphere Changing?

The atmosphere makes the stars twinkle, like it makes the photons sometimes reach your eyeball and sometimes not. It doesn't cause the stars to twinkle, just causes them to be somewhere other than where they appear to be. Another really interesting effect called stellar aberration means that the stars are not actually they look like they are because they have relative velocity to the earth. Altogether, that's more like a bob of black stellar aberrations.