The transit method is a method that is used to detect the star or a planet system and has orbits aligned to each other and the planet travel between the planets and the star and it temporarily blocks some of the light each time in orbit.
And this dimming of the light can help us identify the size of the planet as a star will create slight dimming light while a large planet will have a noticeable effect. And this method can be used to calculate the planets density and composition and mass.
The primary transit is when the planet passes in front of the star and the secondary transits are when it completely disappears behind the planet while the brightness dimes more in at the third and second time the star passes by.
