Chemical Nature of Celestial Bodies
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             DOUBT ?                                     SPECTROSCOPY              

Auguste Comte(1798-1857)Also founder of Sociology

One of the most influential philosophers of the first half of the nineteenth century. A prominent figure in Positivism which has as a central tenet that scientists should not waste their time or energy in attempts to answer unanswerable questions. He believed that stellar astronomy, as opposed to planetary astronomy was a useless exercise because we could never investigate the chemical composition of the stars.
In his Cours de philosophie positive (1830-42) he wrote

" ... to attain a true idea of the nature and composition of this science,
( astronomy) it is indispensable to set aside the vague definitions of it that are still being given, and to mark the boundaries of the positive knowledge that we are able to gain of the stars.
Of the three senses that reveal the existence of distant bodies ,  that of sight is clearly the only one applicable to the celestial bodies.  Any research that is irreducible to actual visual observation is necessarily excluded in regards to the stars,... we can never by any means investigate their chemical composition... the positive knowledge we can have of the stars is limited  solely to their geometrical and mechanical properties.

"It is therefore necessary that we separate more completely than is commonly done the solar from the universal point of view, the idea of the world from that of the universe: the first is the highest we can actually attain , and it is also the only one that truly interests us."

In his book Traite philosophique d'astronomie populaire ( 1844) he wrote

" in the eyes of those for whom science consists of real laws and not of incoherent facts, the second( stellar astronomy) exists only in name, and the first( solar astronomy) alone constitutes the true astronomy; and I am not afraid to assert that it will always be so.

Brief Chronology of Spectroscopy  (reference text)


Spectroscopic Techniques

Modern studies of the universe have a wide range of techniques available which extend well beyond the limits of optical spectroscopy. In fact, these techniques extend beyond the electromagnetic spectrum.

Reference Text                top of page
Modern Theories of the Universe: from Herschel to Hubble, Michael J. Crowe,
Dover Publications, New York, 1994