https://techcrunch.com/2019/12/18/europes-space-agency-just-launched-a-satellite-to-study-planets-outside-our-solar-system/

The European Space Agency (ESA) launched a satellite early this morning, aboard a Russian Soyuz rocket that took off from the Guiana Space Center in French Guyana. Atop the Soyuz is the so-called “Characterizing Exoplanet Satellite” (CHEOPS for short) that will deploy to orbit around Earth, where it’ll have a better view of nearby stars that we’ve previously determined have planets in their own respective orbits.

CHEOPS will specifically be looking to spot the ‘exoplanets’ (planets that are outside our own solar system) as they pass in front of their stars – at which point they become observable because they block some of the light emitted from the distant suns. The satellite will be looking to track large planets in particular, with sizes ranging from larger than Earth to those closer to our own medium-large gas giants like Neptune.