-Red shift is used to detect the distance of planets that are too far to be measured in convential ways
Why is it called Red shift?
-The furthur away galaxies are the more red their appearance is due to their higher wavelengths. The longer the wavelength the longer the lightrays take to travel to earth therefore they are more distant compared to other galaxies
How does Red Shift Work?
-Red shift works via measuring the wavelength of the galaxy. The colour spectrum tells us that the longer the wavelength the more the colour shifts towards red with blue being the shortest wavelength. This can therefore be used to detect the distance of galaxy as the red and long wavelength indicates that the galaxy is very far way compared to a blue and short wavelength planet
What must blue shift mean then?
-Blue shift is the effect of a galaxy coming closer as their wavelength beings to shorten meaning the light rays are quicker to arrive at earth and are therefore closer meaning the galaxy is closer
Look at this spectrum is this an example of red shift or blue shift?
-red shift as the lines depict the galaxy moving towards the red
-If the images were reversed bottom being 1st image top being 2nd then it would be blue shift
