Charles Francis Richter Charles Francis Richter Charles Francis Richter (); April 26, 1900 – September 30, 1985) was an American seismologist and physicist. Richter is most famous as the creator of the Richter magnitude scale, which, until the development of the moment magnitude scale in 1979, quantified the size of earthquakes. Inspired by Kiyoo Wadati's 1928 paper on shallow and deep earthquakes, Richter first used the scale in 1935 after developing it in collaboration with Beno Gutenberg; both worked at the California Institute of Technology. The quote "logarithmic plots are a device of the devil" is attributed to Richter. Richter was born in
Absolute magnitude using an absolute magnitude, one must specify the type of electromagnetic radiation being measured. When referring to total energy output, the proper term is bolometric magnitude. The bolometric magnitude usually is computed from the visual magnitude plus a bolometric correction, . This correction is needed because very hot stars radiate mostly ultraviolet radiation, whereas very cool stars radiate mostly infrared radiation (see Planck's law). Some stars visible to the naked eye have such a low absolute magnitude that they would appear bright enough to outshine the planets and cast shadows if they were at 10 parsecs from the Earth. Examples