The Kepler #Space telescope has been one of the most successful NASA space missions in history, having discovered thousands of planets orbiting other stars by measuring how light from these suns dips when the planets pass between them and Earth. A team of researchers from a number of countries examined these worlds, noting that 216 of them reside in the “habitable zones” around their home stars where the temperature could sustain liquid water, i.e. not too hot and not too cold. Of these worlds, 20 are rocky planets of approximately Earth-size. In other words, Kepler may have discovered 20 planets where alien life might exist.

The next step will be to study these 20 planets to see if any signs exist that they might contain life. The James Webb Space Telescope, due to be launched in late 2018, will be able to help in this regard. The JWST will be able to analyze the atmospheres of these exoplanets by measuring the light of their home stars as they pass through them. Using spectroscopy, the James Webb will be able to detect what elements might exist in these atmospheres by measuring the absorption lines. The presence of water vapor and methane, the latter of what could have a biological origin, would suggest that the planet in question could be habitable.

The Transiting Exoplanet Survey Satellite is due to be launched in December 2017. The TESS will be able to use an array of cameras to detect smaller planets orbiting stars closer to Earth than those found by the Kepler. #NASA hopes that this mission will be able to significantly expand the number of small, rocky worlds which can then be studied by the James Webb and other telescopes, both space and ground based.

However, even larger space telescopes will be needed to really be certain whether an exoplanet contains life. With a large enough mirror, in theory, one could be able to detect continents and oceans on exoplanets. Nothing currently in NASA’s manifest will have this capability. One proposal involves building a telescope on the moon, using moon dust to construct mirrors of 50 meters in length. Using 3D printing techniques, such an observatory could be constructed on the moon, a venue that is ideal for astronomy as it has no atmosphere and provides a stable platform. #KeplerSpaceTelescope