Suppose you are using the Doppler technique to look for planets around another star.What must you do?
A)Compare many spectra of an orbiting planet taken over a period of many months or years.
B)Compare the brightness of the star over a period of many months or years.
C)Carefully examine a single spectrum of an orbiting planet.
D)Compare many spectra of the star taken over a period of many months or years.

Question

Quizplus · Accepted Answer

The Doppler technique involves measuring the small changes in the star's spectrum caused by the gravitational tug of a planet. By comparing many spectra of the star taken over a period of many months or years, any periodic shifts in the spectrum can be detected, indicating the presence of an orbiting planet.

Suppose You Are Using the Doppler Technique to Look for Planets