ESA (European Space Agency) is an intergovernmental agency that coordinates joint space projects for some twenty European countries. Its headquarters are based in Paris and its main technical center in Noordjwick, the Netherlands.
The ESA is the biggest user of parabolic flights in Europe, for the benefit of European research laboratories. It is also the employer of astronauts Jean-François Clervoy (part-time, since he spends the other half of his time at Novespace) and Thomas Pesquet, pilot of the A310 Zero G.