Question

If a star is moving away from you at a constant speed, how do the wavelengths of the absorption lines change as the star gets farther and farther?

Answer 1

Answer:

they stay shifted the same amount to the red

Explanation:

Redshift is given by

$z=\dfrac{\lambda_o-\lambda_e}{\lambda_e}$

Where,

$\lambda_o$ = Wavelength observed

$\lambda_e$ = Wavelength emitted

Also

Transverse redshift is given by

$1+z=\dfrac{1}{\sqrt{1-v^2/c^2}}$

v = Velocity of object

c = Speed of light = $3\times 10^8\ m/s$

So, if the velocity is constant the redshift remains the same