What effect does the Doppler Shift have on starlight from a star moving away from Earth?

The Doppler Shift refers to the change in frequency or wavelength of light from a moving source relative to an observer. When a star is moving away from Earth, the light it emits experiences a shift toward longer wavelengths. This phenomenon is known as redshift.

As the star moves away, the waves of light are stretched, leading to an increase in wavelength. Hence, light that may have originally been in the visible spectrum can shift toward the red end of the spectrum, occurring particularly with wavelengths that are longer than those we would detect if the star were stationary.

This effect can tell astronomers not only about the movement of stars but also about the expansion of the universe. The greater the distance between the star and the observer, the more pronounced this redshift becomes, making it a key factor in studying celestial objects and their velocities.

Thus, the reason the correct response highlights an increase in wavelength directly correlates with the physical principle underlying the Doppler Shift in the context of an object moving away from the observer.