http://blogs.discovermagazine.com/badastronomy/2010/09/29/possible-earthlike-planet-found-in-the-goldilocks-zone-of-a-nearby-star/3) The planets have all been found by the Doppler method: as they orbit the star, they tug on it. This causes a shift in the wavelength of emitted light from the star. The mass of the planet, its distance from the star, and the shape of the orbit all determine how the light shifts, which is how astronomers found those properties of the new planet.
posted number 3 because its crazy how much they can tell just by a shift in the wavelegnth of emitted light from the star.
wonder when we are going to beable to make it to the closest hospitable planet.