Sky brightness and color measurements during the 21 August 2017 total solar eclipse: comment.

While observing the 21 August 2017 total solar eclipse from Shoshoni, Wyoming, the author briefly witnessed an annulus of red light 2° to 3° from the center of the totally eclipsed sun. The author had no prior knowledge of this phenomenon, thus reducing the chances of observational bias. A simple experiment suggests that the phenomenon may not be the result of an afterimage illusion produced by observing the eclipse through binoculars. The results of these observations appear to support the CCD color measurements of the sky during the same eclipse observed from Esterbrook, Wyoming, by Bruns and Bruns [Appl. Opt.57, 4590 (2018)APOPAI0003-693510.1364/AO.57.004590].