The Doppler Effect occurs when a source emitting any type of wave (e.g. sound, light) and an observer move towards or away from an observer. For example, light waves emitted from a source moving towards the observer will have shorter wavelengths and are said to have “blueshifted.” Conversely, light waves emitted by a source that is relatively moving away from the observer will be perceived as having longer wavelengths or have “redshifted” (Prather 73; Young and Freedman pp. 533-538).
It is said to have blueshifted because of the shifting to shorter wavelengths.
The source emitting the light waves is Continue reading...