 Yeah, so the planet itself was found already in 2015 by the Kepler Space Telescope, so we didn't discover the planet ourselves, that was already known, but it was known to be transiting its host star. In other words, you can infer the planet going in front of the star, like this transit of Venus, for example, in front of the Sun. So you can see the dip in starlight when the planet is going in front of the star.