The Doppler Effect is a hoax created by the government to create the illusion of a spherical sun and Earth. Light does not change color as it approaches you or moves away from you. There is evidence that says the Earth is round, but this is false and taught to us since childhood. I know for a fact, simply by looking at my window, that light stays the same color regardless of which direction it it traveling.
I'm sorry, I know you guys are having fun with your "illusions," but I have to address this. The Doppler effect has nothing to do with a round of a flat earth. Neither does it just address light. It addresses ANY energy wave. If a given energy source is moving towards you, the frequency goes up (wavelength get's shorter), which is called a redshift. If it moves away, the frequency drops (wavelength gets longer), this is a blueshift. This can happen with sound, light, radar, radiation, particle beams, or even in something as simple as waves in the water, kinetic energy. You can do a test. Go in your bath tub with your rubber ducky. Bob ducky up and down in the water. Move ducky in one direction, while continuing to bob it up and down. The wave in the direction of travel will be closer together (redshift), and the waves in the opposite direction will be farther apart (blueshift). The Doppler effect has NOTHING to do with the shape of the earth. It was first observed here on Earth, given a name, and then it was figured out that you can use it in relation to light and distant objects (such as stars) to figure out if they're moving towards us or away from us, and how fast.
There's another test you can do. This one is also simple. Stand on the side of a busy street with an audio recording device (or just your ears, if you're a zetetic). When fire trucks, police cars, or anything that makes a loud noise goes by, you can hear that the sound appears to be higher pitched and faster tempo when it is coming towards you (redshift), and lower pitch and slower tempo when going away (blueshift).
There's another test. Get in your car, a speed on the freeway. When a cop pulls you over for speeding, first ask him how he measured your speed. Then ask him how fast you were going. Radar and Laser speed-detectors use the redshift of light to measure speeds. Also, enjoy the speeding ticket.