Wondering what is that electromagnetic wave that greets you on opening the Google home page? It is Google's Doodle marking 155th birth anniversary of German physicist Heinrich Rudolf Hertz.

Hertz through his experiments proved that electricity can be transmitted via electromagnetic waves. It was this discovery that later paved the way toward development of wireless telegraph and radio. In fact, the unit of frequency of a radio wave is called hertz in honour of Heinrich Rudolf Hertz.

Hertz's findings expanded on theory of light put forth by British physicist James Clerk Maxwell in 1884. Hertz measured Maxwell's waves and showed how the velocity of radio waves is equal to the velocity of light. He also calculated the electric field intensity and polarity.

Through his experiments, Hertz expanded the field of electromagnetic transmission. He proved how radio waves can travel through different types of media, which later helped in the development of radar technology.

Hertz was born in Hamburg, then a sovereign state of the German Confederation, into a prosperous Hanseatic family. He studied science and engineering in the German cities of Dresden, Munich and Berlin. In 1880, Hertz completed his PhD from the University of Berlin.

Google Doodles are the decorative changes that are made to the Google logo to celebrate holidays, anniversaries, and the lives of famous artists and scientists. The first Google Doodle was created by Larry Page and Sergy Brin in the year 1998 to mark the celebrations of the Burning Man Festival. Google currently has over 1000 Doodles.

Source ToI