What is Electromagnetic Energy?

What are the Colors of a Rainbow?

Electromagnetic Energy The Earth receives energy in the form of radiation in the following types of wavelengths( radio, infrared, visible light, ultraviolet, x-rays, and gamma rays) .

What Gives off EM Energy? All objects above absolute zero give off EM energy The amount of EM energy given off depends on the temperature of the radiating source

Shorter wavelengths carry more energy

The Colors of Stars is Dependent on the Temperature and the amount of EM Energy given off

Coolest Stars Hottest Stars Blue Red

Why is the Sky Blue? Sunsets Red?

The Sky is Blue because.... During the day sun is closer so the shorter blue wavelengths are scattered by the dust in the atmosphere. Larger particles such as water droplets can scatter most wavelengths leaving the sky looking white (combination of all colors) At higher altitudes there are less particles to scatter the wavelengths so the outer space is black

Sunsets are Red b/c As the distance btn the sun and earth increases only the longer wavelengths of light (red, orange, and yellow) reach the earth and most of the blue light is diluted

How does the “Big Bang Theory” Relate to the Electromagnetic Spectrum? Scientists believe the Solar system formed as a result of a large explosion of gas and matter

Evidence for the Big Bang Red shift – as we observe stars they appear to be shifting toward the red wavelength of light (longer wavelengths) So they are still moving away as a result of the initial explosion and the longest wavelengths of light are reaching the earth.

What would Happen if the Universe was Contracting? We would see the stars shift toward the Blue end of the visible light spectrum.