Green Flash Sequence Observed from Civitavecchia, Italy

February 16, 2021


Photographer: Marco Meniero
Summary Author: Marco Meniero

Shown above is a green flash sequence that I observed at sunset on November 22, 2020. I took 280 shots of the solar disk during the last 5 minutes before it cleared the horizon at Civitavecchia (Rome) Italy. The camera is facing out over the Tyrrhenian Sea. I used the six best images of the green flash for this composition.

A flash of green light can sometimes be detected on the Sun’s upper rim as the solar disk approaches the horizon (rising or setting). The emerald color is due to atmospheric dispersion. In essence, different colors of visible light are bent different amounts, with the shorter wavelengths, including blues and greens, refracting more strongly than the longer wavelengths. Note that the black band resembling Pacman's mouth is in actuality a cloud positioned just above the horizon.

Photo Details: Canon EOS 1DXMk2 camera; set in annual mode with 14fps and 50Iso burst; Canon EF400 lens; f / 2.8; image amplifier (AMPLI by COMA) that pulled the focal length up to 4500 mm