Scientists first confirmed the existence of planets around other sun-like stars in 1992 when they discovered exoplanets orbiting around the star PSR B1257+12. As of 2014, 1,810 exoplanet discoveries have been confirmed by astronomy bodies.
After the 1992 discoveries, a third planet was discovered and confirmed in 1994, followed by discoveries in 1995 and the first discovery of a multiple planetary system in 1999.
In addition to confirmed discoveries, NASA's Kepler mission catalogues possible planetary objects, identifying over 2,900 potential planets as of early 2014.
Scientists search for exoplanets using techniques in direct imaging, transit observations, the Doppler method, astrometry, pulsar timing and polarimetry.