What the Doppler Effect Tells Us About Distant Stars and Planets
Police officers, air traffic controllers, and astronomers all use the Doppler Effect to determine the speed of an object as it approaches or recedes from their radars or telescopes. The frequency (or pitch, for sound) of waves coming from a moving object is changed an amount directly proportional to the speed of approach or recession. The effect of the change, to raise or lower the frequency, specifically indicates that the source is approaching or receding, respectively.
Stephen J. EdbergDate Accepted: 2005-10-24 Grade Group: High School (9-12) Benchmarks: M4.4.2 M4.4.6 M5.4.4 M5.4.16 S12.4.3 Keywords: planet planet search planet mass planet transit doppler effect Microsoft Word: 06_09_05_1.docx PDF Document: 06_09_05_1.pdf