The flag of Mongolia is a vertical tricolor with a red stripe at each side and a blue stripe in the middle, with the Mongolian Soyombo symbol centering on the leftmost stripe. The blue stripe represents the eternal blue sky, and the red stripes symbolise thriving forever. The Soyombo symbol is a geometric abstraction that represents fire, sun, moon, earth, water, and a Taijitu symbol representing the duality of yin and yang.

The current flag was adopted on January 12, 1992, with the current official color standards being set on July 8, 2011. Prior to 1992, the flag had a communist star above the Soyombo, during the final 47 years of the Mongolian People's Republic.

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