The Cheops spacecraft in the Large European Acoustic Facility

The Cheops (CHaracterising ExOPlanet) spacecraft in the Large European Acoustic Facility (LEAF) test chamber at

ESA's European Space Research and Technology Centre (ESTEC) in Noordwijk, the Netherlands, on 7 September,

2018.

The Cheops spacecraft is currently undergoing a series of acoustic testing.

Cheops will observe bright stars known to host exoplanets, in particular Earth-to-Neptune-sized planets, anywhere in the sky. It will study the dip in brightness of a star as a planet transits in front of it, allowing the size of these planets to be determined. Combined with mass measurements already calculated from other observatories, Cheops will enable the planet’s density to be determined, and thus make a first-step characterisation of the nature of these worlds.