A later observation of the object from question 2 was made and it was discovered that the dark lines are shifted by 15 nm to longer wavelengths than expected. a) What does the shift in the wavelength tell us about the motion of the object? b) A second star is observed to have its lines shifted by 20 nm to shorter wavelengths. Which of these two stars is moving the fastest?

A later observation of the object from question 2 was made and it was discovered that the dark lines are shifted by 15 nm to longer wavelengths than expected. a) What does the shift in the wavelength tell us about the motion of the object? b) A second star is observed to have its lines shifted by 20 nm to shorter wavelengths. Which of these two stars is moving the fastest?