Red Stars Versus Blue Stars
Astrophysicists use Doppler effect to determine whether a celestial body is moving towards us or away from us. An object that moves away from us is Doppler redshifted since its observed wavelength is greater than its actual wavelength. Similarly, an object that moves towards us is Doppler blueshifted, since its observed wavelength is less than its actual wavelength.
True or false:
Stars such as Betelgeuse, and Antares, appear red because they are moving towards us. Similarly, stars such as Rigel, Sirius, and Vega appear blue because they are moving away from us.