The Space Shuttle Discovery made a perfect lift-off today carrying ESA astronauts Claude Nicollier and Jean-François Clervoy and five US astronauts into
space. Lift-off from launch pad 39B at the Kennedy Space Center, Florida, occurred at 19:50 EST local time on Sunday 19 December (01:50 Central
European Time on Monday 20 December) at the beginning of a 42-minute launch window.

They are on a 8-day mission to service the orbiting Hubble Space Telescope. The European scientific community is waiting anxiously for the telescope to be
returned to full operation.

Nicollier is set to become the first European to walk in space from the Space Shuttle. On Thrusday 23 December, Nicollier will step out of the Shuttle’s
airlock, help fit a new main computer, a replacement fine guidance sensor which will allow fine pointing and keep Hubble stable. Clervoy will operate the
Shuttle’s robotic arm during demanding phases of the mission, including initial capture of the satellite and for the spacewalks.

Nicollier is on his fourth flight into space. Among them he took part in the first Hubble servicing mission in 1993, controlling the Shuttle’s robotic arm while
astronauts outside performed repairs to the telescope. This time Clervoy, on his third flight, will have the lead role in the operation of the robotic arm.

A vital part of the mission is to replace the telescope’s six gyroscopes which help stabilise the giant observatory during observations of distant astronomical
objects.

Hubble requires three of its six gyroscopes to operate properly for accurate stabilisation but a fourth failed in November posing no long term threat to the
telescope but meaning observations had to be suspended until replacements are fitted.

Discovery’s mission is scheduled to last almost 9 days with a landing targeted to occur at the Kennedy Space Centre Shuttle Landing Facility on Sunday 26
December at 18:25 EST local time (Monday 27 December 00:25 CET).

Hubble was launched in 1990 with an expected orbital lifetime of 20 years. ESA contributed a 15 percent share to its development and in return European
astronomers receive a guaranteed 15 percent share of observing time but in reality this has averaged 20 percent because of the high quality of proposals from
scientists in Europe.

For further information please contact :

ESA Public Relations Division

Tel: +33(0)1.53.69.7155

Fax: +33(0)1.53.69.7690

Further information on HST and the ESA science programme can be found on the worldwide web at : http://www.sci.esa.int