Document 1850694

•The Doppler effect can be used to
determine how fast stars or galaxies are
approaching or moving away from Earth.
When a star or galaxy is approaching Earth,
the lines in its
spectrum are shifted
toward the shorter
(bluer) wavelengths.
When the star or
galaxy is moving away,
the lines in its spectrum
shift toward the longer (redder) wavelengths.
•The larger the shift, the greater is the
speed.