Essential Question  How do astronomers use the electromagnetic spectrum to study the universe?

 Electromagnetic Spectrum The range of radiant (light) energy arranged in order of wavelength and frequency

 Wavelength The distance between to crests of a wave

 Frequency A count of the number of crests that pass a point in a given amount of time High frequency = high energy

Radio Waves Transmitted by a radio station Astronomers use them to study what stars are made of, their structure and movement

 Microwaves Used to cook your food Used to learn about galaxies Used to learn about stars that are behind clouds of dust

 Infrared Waves Used by astronomers to map dust between stars There are 2 types: ○ 1 comes from the heat from the sun ○ 1 is used in any device that has a remote control

 Visible Light Rainbows show the different wavelengths of light We are able to see colors of stars which gives us a clue about their temperature Helps us understand the Red Shift and Blue Shift

 Ultraviolet Rays Newly formed stars give off UV rays Used to learn about the structure and how galaxies change Causes you to get sunburned

 X-Ray Wave Black holes give off X-Ray waves Used in hospitals and doctors offices

 Gamma Rays Given off from any explosion like a supernova or a black hole Astronomers use them to gain knowledge of how our universe began and how fast it is expanding

Radio Waves: The Sun

X-Ray: Andromeda Galaxy

Infrared: Constellation Orion