They're light years away, man, and that's pretty far (lightspeed's the limit, the big speed limit) But there's plenty we can learn from the light of a star (split it with a prism, there's little lines in it) By looking at the spectrum at the light that's glowing (wavelengths of emission, measured with precision) Its Doppler Shift will tell us if it's coming or going Doo doo doo doo doo-ooo That's the Doppler Shift - you see it, it's true Doppler Shift - to the red or the blue When a star is approaching and it's coming our way Its spectrum seems bluer, won't you hear what I say And when a star's retreating way out of range And the scientist measures its frequency change Well that's a redshift, redshift If the star is moving away By reading Doppler Shifts of all we see in the skies (clusters of galaxies, near and far) We get the big picture and a big surprise (redshifts going, redshifts going) The Universe is growing and expanding away (galaxies are speeding, speeding away) But maybe gravity will shrink it back some day Owwwwwwwwwwwww-eeeeeeeeeee Doppler Shift