Question

The spectrum of a star shows a set of dark absorption lines equivalent to the absorption lines of the Sun but with one exception: Every line appears at a slightly longer wavelength, shifted toward the red end of the spectrum. What conclusion can be drawn from this observation

Answer 1

Answer:

The shift in the emission spectra of the relative velocity between the star and our planet, is called the relativistic doppler effect

Explanation:

The absorption and emission spectra are measured differently, the emission spectrum is the spectrum emitted by the star and the absorption spectrum is the absorption of these lines by the gases of our atmosphere, this absorption occurs for relatively broad Δλ.

The shift in the emission spectra of the relative velocity between the star and our planet, is called the relativistic doppler effect and has a red shift if the star moves away from us.

           $f_o = f_s \sqrt{\frac{1- v/c}{1 + v/c} }$