Pursuing this line of research, Kirchhoff deduced the existence of three types of spectra: The continuous spectrum, the emission spectrum and the absorption spectrum.

Kirchhoff’s discoveries opened the doors to spectroscopic studies in astronomy. To their great satisfaction, astronomers were now equipped with a method for determining the chemical composition of stars and nebulas, and even their temperature, distance, speed and age by measuring the intensity of the different spectral rays and applying basic principles of physics. It was through spectroscopy that light allowed us to “touch the stars”, something long believed impossible due to the great distances involved.

One problem remained unanswered for Kirchhoff: he could not explain how matter could emit or absorb light. Other researchers would help resolve this enigma 50 years later.
ASTROLab of Mont-Mégantic National Park

© 2006 An original idea and a realization of the ASTROLab of Mont-Mégantic National Park

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