Blueshift is observed when
*
1 point
a luminous object travels alongside an observer
a distant luminous object travels rapidly towards an observer
a distant luminous object travels rapidly away from an observer
a luminous object is stationary compared to an observer
Blueshift is observed when a distant luminous object travels rapidly towards an observer.
Blueshift is observed when a distant luminous object travels rapidly towards an observer.
Blueshift is observed when a distant luminous object travels rapidly towards an observer.
To understand why this happens, we need to consider the concept of the Doppler Effect. The Doppler Effect is the change in frequency of a wave (in this case, light) due to the relative motion between the source of the wave and the observer.
When a luminous object is moving towards an observer, the waves of light emitted by the object are compressed, causing the observed wavelength to appear shorter. Remember, shorter wavelength corresponds to higher frequency according to the formula v = λf (where v is the velocity, λ is the wavelength, and f is the frequency). In the case of visible light, higher frequency means shifting towards the blue end of the visible spectrum, hence the term "blueshift."
In contrast, when a distant luminous object travels rapidly away from an observer, the waves of light get stretched, resulting in an observed wavelength that is longer. This shift towards longer wavelengths is called redshift.
It is worth noting that the magnitude of the shift depends on both the speed of the object and the observer's distance from it. The faster the object moves toward the observer, the greater the blueshift observed.
In summary, blueshift is observed when a distant luminous object travels rapidly towards an observer, causing a compression of the light waves and a shift towards shorter wavelengths, specifically towards the blue end of the spectrum.