Tune in to ESA Web TV from 08:30 GMT (09:30 CET) Wednesday 18 December to watch ESA’s exoplanet mission soar into space on a Soyuz-Fregat rocket from Europe’s Spaceport in Kourou, French Guiana.

Cheops, the Characterising Exoplanet Satellite, is scheduled for liftoff at 08:54 GMT (09:54 CET) on its exciting mission to study planets orbiting stars other than the Sun. It is ESA’s first mission dedicated to the study of exoplanets.

Cheops will observe bright stars that are already known to host planets, measuring minuscule brightness changes due to the planet’s transit across the star’s disc. The mission will target Earth- to Neptune-sized planets and will provide information about the character of the planets: that is, if they are rocky, gassy, icy or perhaps harbour oceans. This is a critical step in understanding the nature of planets beyond our own Solar System.

Cheops shares the ride into space with the Italian space agency’s Cosmo-SkyMed Second Generation satellite and three CubeSats: ESA’s OPS-SAT and the French space agency’s CNES's EYE-SAT and ANGELS satellites.

Cheops is scheduled to separate from the upper stage at 11:19 GMT (12:19 CET). The first opportunity for acquisition of signal is expected some 30-40 minutes later, and will be announced from the Mission Operations Centre located at INTA, Spain.