The phenomenon of halo around the sun and moon occurs mainly because ice crystals suspended in some clouds refract light, creating special shapes in the sky. The most famous and conspicuous is the 22 degree halo like it just appeared in Ba Ria - Vung Tau. But in other parts of the world, there are many kinds of light appearing inside and outside the halo of 22 degrees.
In a photo posted by NASA on February 24, 2020, a beautiful moon aura with both corona, halo 22 degrees and moon dogs appeared in Manitoba, Canada - (photo: Brent Mckean)
On April 1, 2015, both the sun and the moon appeared in Ostersund, Sweden - (photo: Göran Strand)
The 22-degree halo is created by refraction of six-sided cylindrical ice crystals. Inside it may also appear multicolored rings called "corona" , caused by quantum diffraction by small droplets of water or ice near the sun / moon. In addition to the 22 degree halo, there may be additional "sun dogs" and "moon dogs" in the form of magical bands created by light refracted through thin, flat, six-sided ice platelets as they fly towards the face. land.
Aura of the moon in Pennsylvania, USA April 2003 - (photo: Sarah McKay)
Incredibly complex, breathtaking solar aura taken between January and January2020 in the Swiss glaciers - (photo: Michael Schneider)
The afterglow of the sun in Yellowknife, Northwest Territories, Canada, September 2018 - (photo: Martin Male)
Aura of the moon in a deserted area near Marid, Spain in December 2012 - (photo: Dani Caxete)
According to NASA, this optical phenomenon is not common and usually only pants 22 degrees. The halo bigger than the second (halo 46 degrees) is very rare, especially for the moon aura. This phenomenon usually lasts a few minutes to several hours.