Doppler Effect

You may already know that stars and other celestial objects move in space, but did you know that astronomers can actually tell whether or not they are approaching the Earth or moving away from it, and at what speed they are moving? Astronomers take advantage of the what is known as the Doppler effect of waves to make such calculations. It is another way that stars and other faraway objects can be studied from various positions on Earth.

Essential Questions

• What is the Doppler effect, and how does it apply to astronomy?
• What is the difference between redshift and blueshift?
• How do the expansion of the universe and the Big Bang Theory relate to Doppler and redshift?