Look Who it Was Random video

Christian Doppler Google Doodle

2,969 views · Published 29 November 2017 · 2:16 · Indexed 23 October 2026

Channel: Rajamanickam Antonimuthu · 2017 · Science & Technology

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The Search Engine Google is showing this doodle in Germany for Christian Doppler’s 214th Birthday.
Christian Doppler was an Austrian mathematician and physicist. He is celebrated for his principle — known as the Doppler effect — that the observed frequency of a wave depends on the relative speed of the source and the observer. He used this concept to explain the color of binary stars.

When a fire engine approaches, the siren gets louder as it comes closer, taxing your eardrums as it whizzes past, and fades into the distance. What causes this difference in volume?

The answer was proposed by  Christian Doppler in 1842 in a phenomenon since documented as the Doppler Effect, a concept that applies to both sound and light, in addition to other phenomena.

Simply put, sound is generated in ‘waves.’ As the source of such waves moves closer, the waves themselves take less time to reach you. They hit you with increasing frequency, making the sound more intense. As the source moves away, the waves start to spread out, and the sound becomes weaker.

The Doppler effect also explains why stars in the sky appear to be of different colors. As a star approaches the earth, wavelengths compress and the star appears to be bluer in color. If the converse happens and a star is moving away from us, it appears redder.

Though the Doppler Effect is his most famous contribution to scientific literature, Christian Doppler authored over fifty works in mathematics, physics, and astronomy over the course of a twenty year teaching career that spanned modern day Austria, the Czech Republic, and Hungary.

Today’s Google Doodle   celebrates Christian Doppler’s 214th birthday. It shows Doppler in Salzburg, his native city, holding an airplane as it creates a Doppler effect.

Read more details about Christian Doppler at https://en.wikipedia.org/wiki/Christian_Doppler
See the Google Doodle for Christian Doppler’s 214th Birthday at https://www.google.com/doodles/christian-dopplers-214th-birthday

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