Question

Task: You need to show and explain the evidence that suggests that the universe is changing.

Answer 1

Well you know stars are moving around due to red and blue shifts. It's similar to the Doppler effect, but with light. If a star is moving towards you, it ever so slightly "decreases" the wavelength of the light it emits as its moving in the direction of the radiation. You perceive apparently this apparently shorter wavelength as blue, so the star has a bluish tinge. Similarly, if the star is moving away from you, it is moving in the direction opposite the light from it that you see. Therefore, it ever so slightly increases the wavelength of the light moving towards you, and you perceive it as red. If the star was moving perpendicular to you, you would probably see its "real" colour as the wavelength of the light emitted in your direction is not being changed.

Answer 2

In fact, the faster an star is moving towards you/away from you, the bluer/redder it appears due to the increased compression/increased expansion of the light waves.