The Kepler space observatory proved the effectiveness of the transit technique in finding exoplanets. After losing one reaction wheel too many, it was assumed that Kepler was an ex-exoplanet finder. However, the clever Kepler scientists and engineers found a way to use solar radiation pressure to keep the telescope steady in its viewing of distant stars. Now renamed the Kepler K2 mission, the observatory continues its planet spotting, albeit less efficiently than before.

So Kepler keeps adding to the list of exoplanets for now but a whole new improved exoplanet hunter is expected to go to space in August 2017. TESS (Transiting Exoplanet Survey Satellite) will monitor more stars than Kepler and it should also do better at finding small planets, i.e. earth-sized ones, orbiting around them. TESS will monitor

the brightnesses of more than 500,000 stars during a two year mission, searching for temporary drops in brightness caused by planetary transits. Transits occur when a planet’s orbit carries it directly in front of its parent star as viewed from Earth. TESS is expected to catalog more than 3000 transiting exoplanet candidates, including a sample of ∼500 Earth-sized and ‘Super Earth’ planets, with radii less than twice that of the Earth. TESS will detect small rock-and-ice planets orbiting a diverse range of stellar types and covering a wide span of orbital periods, including rocky worlds in the habitable zones of their host stars.

Here’s a video overview of the project:

We can also hope it has much better and more numerous reaction wheels…