Triple Halo Event - 22° Circular Halo, 9° Halo, and Circumscribed Halo

July 15, 2022

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Photographer: Meiying Lee

Summary Author: Meiying Lee

The photo above features a beautiful solar halo as viewed from the top of the 7,545 foot (2,300-meter) Jhenshan trail near Hsinchu, Taiwan. Taken at noon local time, the altitude of the Sun was around 60° above the horizon. First, I noticed the 22° circular halo and circumscribed halo. After looking for a few moments, I also saw the strong 9° halo. I was so happy to see both halos! It was especially exciting to spot the 9°halo, which is one of the 'Odd radius halos'.

The difference between the two halos is the 9°halo was likely formed by pyramidal shaped ice crystals, which are not very common. Whereas the 22° circular was a result of comparably more common occurring plate or column ice crystals. Later, I saw there are some white arcs outside the larger 22° halo. If you look closely, it turns out to be a parhelic circle passing through the Sun, shown more clearly in the second photo.  

Photo details: Apple iPhone 13 Pro, f/1.8. ISO-25, 1/9346 second exposure, 2mm focal length