|Christian Johann Doppler
(1803 – 1853)
On November 29, 1803, Christian Johann Doppler, Austrian Physicist and mathematician was born in Salzburg.
Doppler was born into a family of stonemasons, but due to his weak physical appearance, he was not able to continue in the family’s business and was occupied mostly with a bookkeeping position. It was noticed, that he developed great talents in the field of mathematics wherefore he began his scientific career at the Polytechnic Institute in Vienna. His first major papers were published in the 1830’s and became Professor for mathematics and practical geometry at the Prague Polytechnic in 1841.
The presentation of his work ‘Über das farbige Licht der Doppelsterne’ (Concerning the colored light of the double stars) at a meeting of the Natural Sciences Section of the Royal Bohemian Society in Prague promised a break through for the young scientist. The paper depicted his first presentation of the famous Doppler Effect, relating a frequency of a source to its velocity relative to the observer. He explained, how a ‘sound pitch from a moving object differs from an observer with a fixed position and that therefore the color of the light from a star should alter according to the star’s velocity relative to Earth’. Doppler described that every ‘star emitted white light and that the color of some stars was owing to their motion toward or away from us’.  This theory was later confirmed by a meteorologist, who used a locomotive carrying several horn players. He detected the predicted pitch of the notes as the players approached and hurried away. The Doppler Principle was applied in various fields beyond astronomy. In medicine it was used to detect cardiac motion and cardiac valves or to investigate the fetal blood flow just to give some examples.
Doppler became famous very fast due to his researches and found himself at the highest point of his career in 1850, when appointed as the first director the the Institute of Physics at the Imperial University of Vienna. Unfortunately his life long health issues did not improve and after catching tuberculosis he passed away at the age of only 50.
His name name and research remains in many aspects of physics, and astronomy. Next to the Doppler Effect, he has published numerous works on electricity, magnetism, optics, and astronomy in his life and was known to be a revolutionary thinker, although some theoies would not work out in practice.
At yovisto you can learn more about the Doppler effect in MIT Professor Walter Lewin’s lecture on Physics, where he discusses its principles.
References and Further Reading:
-  Christian Johann Doppler: the man behind the effect, The British Journal of Radiology, 75 (2002), 615–619
- The Doppler Effect at Science World
- Christian Doppler Biography