On August 5, 2023 at 20:35 I witnessed an extremely rare event, namely a lower mirage of a green flash formed. Both events are rare, and their simultaneous formation is even rarer.
Let’s see in detail what it is:
What the green ray is: a green streak that appears on the top of the solar disk. It forms due to various physical causes such as atmospheric refraction, dispersion, selective absorption and Rayleigh scattering. It can be considered a special case within the mirage family.
What mirages are: the atmosphere acts like a lens, bending light rays and creating distorted, inverted and shifted images. Mirages can be inferior, superior or mixed (like the Fata Morgana). The inferior mirage consists of seeing the image flipped downward. In the case of this photo we have an inferior mirage: in fact the green ray is also seen below the solar disk. This green portion does not exist, but is only an optical distortion due to the mirage.
Well, I was lucky enough to witness an inferior mirage of a green ray:
By looking closely at the image you can see the very sharp green ray on the upper edge of the solar disk at sunset. At the base of the Sun another green streak appears, but we know that in that position the green rim cannot occur, so this is simply the inferior mirage of the green flash that appeared above. The atmosphere acted like a mirror.
Shooting data:
Nikon Z9 in APS-C mode at 200 ISO, Nikon Z 400 f/4.5 with 2X, equivalent focal length 1200mm, shutter speed: 1/3200. Shooting location: Marina di Pisa, Pisa, Italy
On August 5th at 8.35pm I witnessed an extremely rare event: a lower mirage of a green flash was formed. Both events are rare and the contemporary formation is more so.
Let's see in detail what it is:
What is the green ray: a green streak that appears on the top of the solar disk. It is formed due to various physical causes such as atmospheric refraction, dispersion, selective absorption and Rayleight scattering. It can be considered a special case of the mirage family.
What are mirages: the atmosphere acts like a lens, deflecting light rays creating distorted, inverted and displaced images. Mirages can be inferior, superior or mixed (like the Fata Morgana). The inferior mirage consists of seeing the image reversed downwards. In the case of this photo we have a lower mirage, in fact the green ray is also observed under the solar disk. This portion of green does not exist, but is only an optical distortion due to the mirage.
By carefully observing the image you can observe the very clear green ray on the upper edge of the solar disk during sunset. Another green streak appears on the base of the Sun, but we know that the green rim cannot occur in that position, so this is simply the lower mirage of the green flash that appeared above. The atmosphere acted like a mirror.
Data: Nikon Z9 in APS-C mode at 200Iso, NikonZ400 f/4.5 with 2X, equivalent focal length 1200mm, exposure time equal to 1/3200. Shooting site, Marina di Pisa, Pisa, Italy
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