Some researchers have already started thinking about how they might use instruments like the planet-hunting KeplerSpaceTelescope to detect alien moons.
This past December, for example, NASA's Keplerspacetelescope confirmed its first planet in the habitable zone, a "super Earth" known as Kepler-22b that's thought to be 2.4 times as wide as our planet.
Dubbed the Transiting Exoplanet Survey Satellite (or TESS), this new spacetelescope will one-up Kepler with the ability to perform an all-sky survey (an area 400 times larger than previous missions) to search for transiting exoplanets, with an eye towards planets comparable to Earth in size.
It was set up by a group at the universities of Oxford and Yale, and links 40, 000 participants with data gathered by Kepler, another NASA spacetelescope that is specifically designed to hunt for planets.