Thursday, February 18, 2016

18 February 2016- Redshift | PWN Physics 365

A On this day in physics: 18 February 1745- Happy Birthday to Alessandro Giuseppe Antonio Anastasio Volta, who turns 271 today. The inventor of the "voltaic pile" which was an early version of the battery. He invention pretty much started the entire field of electrochemistry.

Word of the day- Redshift- Is a type of doppler shift which occurs with cosmic light. Like yesterday's word of the day, the same idi applies with light. When light moves away from the observer, the wavelength gets longer, or shifts to the red side of the spectrum. It is possible to analyze the light from galaxies, if the light is redshifted, astronomers can decipher whether or not galaxies are moving away from us or not. When analyzing starlight, it is possible to identify critical frequencies which we know to be emitted from different elements. If the wavelength of the light is, for example, several nanometers longer than potassium, we know that potassium exists in the star and that it is moving away from us.

Quote of the Day: "If you want to make an apple pie from scratch, you must first create the universe." -Carl Sagan

Keywords: Redshift, Light, Doppler, Shift, Relativity

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