Answer:
The primary method by which the planets have been found around other stars in the galaxy is Kepler Space Telescope.
Explanation:
The primary method by which planets have been found around other stars in our beautiful Galaxy is the Kepler space telescope. Kepler launched Kepler Telescope in 2009 to help to find terrestrial planets super-earth etc.
This is the telescope which measures the amount of light coming from a star and detects a slight variation in brightness as a planet passes in front. Using this technique NASA's Kepler Mission has founded thousands of candidate planet in this world.