Rainbow Flashes
June 09, 2022
Photographer: Dario Giannobile
Summary Author: Dario Giannobile
This photo compilation features an optical effect called Green Flash for the planet Mars and star Dschubba. Green ray is a phenomenon caused by the refraction of incoming light as it passes through thick layers of the atmosphere. Shorter wavelengths refract more strongly than longer red wavelengths, and color separation gives a green hue to the last visible ray of our luminous object. Green ray evidence is extremely common on the solar disk but much rarer on the Moon and planets. Even more peculiar is a separation of the light that can lead to the observation of a blue-tinted flash. A telescope or telephoto lens and camera can help capture this tantalizing result of atmospheric refraction when celestial bodies are close to the horizon. This one-of-a-kind image shows for the first time the phenomenon in its entirety during the rising of the star Dschubba of the constellation Scorpius (delta Scorpii). Various flashes have been created around the star that have taken on the tints of the rainbow, shifting from red (in the lower edge of the star) to blue / purple in the upper edge. The same phenomenon happened shortly after during the rising of Mars which presented different flashes and colors mainly of red and green.