What is Doppler Effect and how does it determine the velocity of a star like Rigel?

Doppler Effect Explained

The Doppler Effect is a phenomenon observed in waves, where the frequency of the waves changes depending on the relative motion between the source of the waves and the observer. This shift in frequency can be seen in various types of waves, including sound waves and light waves. In the case of analyzing the spectrum of stars like Rigel, the Doppler Effect plays a crucial role in determining the star's velocity relative to Earth.

Analysis of Rigel's Spectrum

When observing the spectrum of a star like Rigel, astronomers might notice a shift in the hydrogen line frequency compared to when it is stationary. This shift is caused by the Doppler Effect, indicating the star's velocity relative to Earth. By analyzing the magnitude of this shift, astronomers can calculate the velocity of Rigel.

Calculating Rigel's Velocity

To calculate Rigel's velocity relative to Earth, astronomers use the Doppler Effect formula, taking into account the frequency shift observed in the star's spectrum. By applying the principles of wave frequency and the speed of light, astronomers can accurately determine Rigel's velocity in relation to Earth.