The Invention of Spectroscopy, the Era of Big Refractors, and the Ascendency of Reflecting Telescopes in the 19th Century

At the beginning of the 19th Century, the spectroscope was invented by Joseph Fraunhofer in Germany, which introduced a way to ascertain the chemical compositions of astronomical objects through remote sensing. Additionally, larger telescopes were being built. This happened with both refractors and reflectors, leading to a competition to see which of these two kinds of telescopes would ultimately become dominant in astronomy. Initially, refractors where the preferred technology, especially after the failure of the Great Melbourne reflector in 1846. As a consequence, numerous large refractor telescopes were built in the latter part of the century. But when new technologies allowing reflector telescope mirrors to be made from glass rather than metal, large reflecting telescopes became more practical and outpaced refractors in their performance. This was especially the case in the U.S., where reflector telescope innovation accelerated hand in hand with the development of the science of astrophysics.

Speaker: Dr. Ken Lum