XMM-Newton was launched the 10 December 1999,on the first Ariane-5 commercial mission, from ESA’s Kourou Spaceport in French Guiana.
ESA's XMM-Newton space observatory is the flagship of European X-ray astronomy. It is the most powerful X-ray telescope ever placed in orbit and is observing the 'hot' X-ray universe including objects like neutron stars, black holes and active galaxies.
More information here
CHEOPS - CHaracterising ExOPlanet Satellite - is the first mission dedicated to searching for exoplanetary transits by performing ultra-high precision photometry on bright stars already known to host planets.
Date of launch: mid-December 2019 tbc
Location: CSG, Europe’s Spaceport (French Guiana)