corona

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Faint halo of hot (about 2,000,000°C/3,600,000°F) and tenuous gas around the Sun, which boils from the surface. It is visible at solar eclipses or through a coronagraph, an instrument that blocks light from the Sun's brilliant disc. Gas flows away from the corona to form the solar wind. It is not certain why the corona is so much hotter than the surface of the Sun (about 6,700°C/12,100°F). The heating may be due to interactions with the Sun's magnetic field, or to pulses of sound waves from the Sun. NASA's Reuven Ramaty High-Energy Solar Spectroscopic Imager mission, launched in 2001, studies the evolution of energy in the corona.

Red recalls the banner of Manas who united the Kyrgyz tribes. The emblem shows a bird's-eye view of a yurt, secured by a lattice of ropes. Effective date: 3 March 1992. >>