Unlike fire on Earth, the sun’s heat is not produced by the oxygen-fed combustion of inflammables. Its fierce, hot energy is actually the by-product of nuclear fusion at the core of the star. The sun is about 70 per cent hydrogen in weight. The enormous gravitational force at its core creates a high temperature and a high density that cause hydrogen atoms to fuse together to become helium. Helium is lighter than the four hydrogen atoms required to make it, and the weight difference is released as energy. That energy takes the form of light, comprised mostly of invisible X-rays and gamma rays. The rays bounce about at random for thousands of years, fighting their way through the sun’s dense, 700,000-km radius. Once at the surface, the now-visible spectrum light zips to Earth in eight minutes, making you squint.
|Monzter on 18 October 2012 ,12:18 |
how do you know this? has anyone ever physically proven it?
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