Doppler effect and Red Shift of star

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Doppler effect

Doppler Effect This is the change in the wavelength and frequency of a wave that is felt by the observer approaching or moving near the source of that wave. You can feel this effect from the changes in the sound of a vehicle approaching you and the sound of a vehicle going away.

Looking at it scientifically, it is that the wavelength of the sound waves of the vehicle going away from you increases, and the wavelength of the sound waves of the vehicle coming near decreases. In other words, the frequency decreases when the wavelength increases and the frequency increase when the wavelength decreases.

Let's take an easy example, suppose one player is throwing a ball every second towards another player. If the other player stands in his place, he will get a ball every second. If the player facing the ball moves away from the throwing player, then the interval of the balls he receives will increase, i.e. the balls he receives every second will decrease. In the language of science, the frequency of receiving the ball will decrease. If the ball-player approaches the throwing player, the frequency of receiving the ball will increase. Note that there is no change in the frequency of throwing the ball of the source.

The same effect occurs on any wave (sound / light / X-ray / gamma-ray). When the wave moves away from the source, its frequency decreases, that is, there is an increase in the wavelength. When the wave comes near the source, its frequency increases, that is, there is a decrease in the wavelength.

Red Shift

Red deviation This process in which the light emitted from a body moves towards the red color in the spectrum. Scientifically, it is an increase or decrease in the frequency of the wavelength of the illumined light ray compared to the emitted light beam. In other words, there is an increase or decrease in the frequency of the wavelength of the light rays until the light reaches the source of light.

Light rays have the highest wavelength of red light rays, hence the deviation of any color ray towards red in the spectrum is called 'red deviation'. This process is also applicable for unpublished rays (gamma rays, X rays, ultraviolet rays) and is known by this name. Rays whose wavelengths are more than red rays (infrared), microwave, radio waves, this deviation is far from red.

Usually, the red deviation occurs when the light source moves away from the light observer, just like the Doppler theory of sound rays! This theory is used in astronomy to measure the speed and distance of celestial bodies.