A branch of astronomy that deals with the origin, structure and space-time relationships of the universe the cosmology as a study manifests visible universe and the non-visible part also.
We humans always thrilled and fascinated by the play of star light which is spectacular to see through eyes to look and feel the cosmic acts which are present in this universe. So my article here presents the stellar spectral importance (SSI).
If history of spectral analysis is checked, we come across on experimenter William Wollaston who was Great physicist. Once passed a beam of sun light through a thin slit and then through a prism. The slit provided familiar rainbow spectrum with no color overlapping each other. When seen, Wollaston noticed, our star sunâ€™s spectrum was having some black lines in it. This was fundamental idea.
The early spectral studies actually began with discovery of so many secrets of lines absorbed by elements in the spectrum of sun. It was absorbed by elements present in the star or sun, an intensive idea was got foundation further by German physicist Joseph Frauhofer in 1814. Bright and continuous spectrum is results of superposition of these lines have been named in honor of the discovery as Fraunhofer lines.
To explain in simple Words for above sentences when metals heated beyond certain temperature, emits white light. The Early stellar spectra showing the Distinctive absorption lines these astronomers used to determine stars composition and temperature. This above method is still in use. This set of spectra comes from the original Henry Draper Catalogue.
But elements can only absorb light that can excite their electrons from one valence bond to another. This is not same for all metals. The frequency and wavelength corresponds to the energy, as the way the missing wavelength will give away the Ionization level or state of energy and the elements is identified.
Thus the composition of the star is determined. But stellar spectroscopy is the study of specter of star light. it is very powerful tool that enables Astrophysicist to infer many Physicical and chemical properties of stars and to divide them in an order which is easier for further analysis.
I personally think that SSI stellar spectral importance is the best discovery in cosmology. This is key to the mysteries present in stars and galaxies.
© Akshay Kumar 
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