Many people assume that astronomers “see” exoplanets directly through their telescopes, perhaps akin to the Earth as a pale blue dot sitting alongside a distant star. The reality is much stranger: in most cases, all that is seen is a single, stationary pin-point of light – the star itself. Yet by measuring the brightness of that speck of light, astronomers may see a tiny repeated dimming, as though the star is winking at us, indicating the transit of an exoplanet in front of the star, blocking a fraction of the light. But just from that faint light, we are able to find out a lot about the exoplanet.
With the help of simple methods and powerful telescopes, astronomers may infer that the star is wobbling back and forth, as it is tugged by the gravity of an exoplanet. From the depth of the “wink” and the amplitude of the “wobble”, the size and mass respectively of the unseen exoplanet can be determined. This can give us its density and surface gravity which in turn tell us what the exoplanet may be made of.
NASA EXOPLANET BULLCRAP
Exoplanets are nothing more than twinkling stars – PATHETIC!
About 97% of all the known exoplanets, have been discovered by indirect techniques of detection, mainly by radial velocity measurements and transit monitoring techniques. The following methods have proved successful for discovering a new planet or confirming an already discovered planet: 
Light variations due to relativistic beaming
Light variations due to ellipsoidal variations