Astronaut Claude Nicollier, mission specialist representing the European Space Agency (ESA), during its training in the Neutral Buoyancy Laboratory (NBL), in July 1999. Nicollier and other astronauts assigned to STS-103 space walk duty are currently training for EVA chores they will handle when they make the third servicing visit to the Earth-orbiting Hubble Space Telescope (HST) since its deployment in April 1990.