Catch a Wave...

Light is electromagnetic radiation whose wavelength can be sensed by the human eye. There are many other wavelengths that can be detected using instruments. The study of electromagnetic wave spectra is called "spectroscopy". Spectroscopy can provide information about the chemistry of planets, the speed of comets, the temperatures of stars, and much more. For example, at infrared radiation wavelengths a heat-generating body is easily detectable against a non-heat-generating background*. Photographs of other planets and stars are only part of the whole picture!!

This chart shows the types of waves and their sizes on a logarithmic scale... that's why the distance between 1 and 10 is the same as the distance between 10 and 100. Each tick mark represents a factor of 10 increase or decrease from the one next to it. For example, Short Waves are 10 times longer than FM & TV waves and visible light is 100 times (two tick marks =10 X 10) shorter than infrared radiation.

How many times larger than bacterium are grains of sand?
How many times larger than bacterium are humans?
Which of Galileo's instruments would you use to take photos of the Great Red Spot? Why?
Could we hear Jupiter's radio emissions?

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Last modified prior to September, 2000 by the Windows Team

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