Twinkling
Twinkling is the term for changes in the apparent
brightness and position of
stars; this is caused by
atmospheric turbulence and various other irregularities. In photographs, twinkling causes an
image to be "smeared" into a "
seeing disk". The effects of twinkling can be, partially, corrected for by
active and
adaptive optics. Twinkling is the subject of the
song Twinkle, Twinkle, Little Star (
1761).
