Understanding the composition of stars
If I know this, I might land as an alien on some other star-world.‘Twinkle twinkle little star how I wonder what you are. Up above the world so high, like a diamond in the sky.’ That’s how we all wondered about stars when we were kids. Earlier it was not possible to know in detail about the stars because of their great distance from the earth. But, in 1814, a discovery by Joseph Fraunhofer, a German scientist made the study of stars very easy. He found dark lines in the spectrum of the sun, which are now known as Fraunhofer lines. He described a large number of the 500 or so lines he could see using self-designed instruments, labeling the most prominent ones with letters, a form of nomenclature that is still in favour. Fraunhofer lines revealed the chemical composition of the atmosphere of sun - the brightest star in our sky. With the help of these lines, composition, temperature and speed of the distant stars can also be known.
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