NASA is planning to launch a new satellite called TESS (the Transiting Exoplanet Survey Satellite) on April 16, 2018, which will be tasked with finding new planets to be studied for atmospheres capable of supporting life, reports the media outlet Science Alert. In this respect, TESS will replace its predecessor Kepler, which surveyed nearly 150,000 stars for planets of different types, some of which were later studied by the Hubble space telescope.
Hubble itself will also be replaced by the JWST (the James Webb Space Telescope) and will have 6.5-meter-wide mirror, capable of collecting more light than Hubble ever could. The space telescope, whose launch is planned in 2020, will be studying so-called transitions — moments when planets pass "in front" of their suns (with respect to the telescope).
Sun rays, passing through the atmosphere are partially absorbed by the molecules in it. By studying the "output" rays scientists can determine the content of the planet's atmosphere. Telescopes on earth can do the same, but the effectiveness of such analysis is greatly hindered by our own atmosphere, while space telescopes receive "pure" data.
But in order to study planets, the JWST needs to know where they are and which may theoretically possess an atmosphere capable of sustaining life — they must not be too far or too close to their sun to have liquid water.
TESS will be the one to find these planets and add them to the database. It will watch each region of space for 30 days, looking for planets that manage to perform a transition during this time frame. Any planet that can do it within such time frame is located at a distance far enough away from their sun for water not to turn into ice, thus giving it a chance to have a life-sustaining atmosphere.