After nearly 12 years of incredible scientific discoveries, the ESA/NASA
Hubble Space Telescope orbiting Earth is about to have another service
visit. The purpose is to upgrade Hubble system and to install newer and
more powerful instruments that will astoundingly increase Hubble’s
discovery capabilities and extend the longevity of the observatory.

As a unique collaboration between the European Space Agency (ESA), and
NASA, Hubble has had a phenomenal scientific impact. The unsurpassed sharp
images from this space observatory have penetrated into the hidden depths
of space and revealed breathtaking phenomena. But Hubble’s important
contributions to science have only been possible through a carefully
planned strategy to service and upgrade Hubble every two or three years.

ESA, the European Space Agency has a particular role to play in this
Servicing Mission. One of the most exciting events of this mission will
come when the ESA-built solar panels are replaced by newer and more
powerful ones. The new panels, developed in the US, are equipped with ESA
developed drive mechanisms and were tested at the facilities at ESA’s
European Space Research and Technology Centre (ESTEC) in the Netherlands.
This facility is the only place in the world whsitysuch tests can be
performed.

According to Ton Linssen, HST Project Manager at ESA, who supervised all
ESA involvement in the new solar panels development including the test
campaign at Estec – “a particularly tense moment occurs when the present
solar panels have to be rolled up to fit into the Shuttle’s cargo bay. The
hard environment of space has taken its toll on the panels and it will be
a very delicate operation to roll them up. Our team will be waiting and
watching with bated breath. If the panels can’t be rolled up they will
possibly have to be left in space.”

“With this Servicing Mission Hubble is once again going to be brought back
to the frontline of scientific technology”, says Piero Benvenuti, Hubble
Project Scientist at ESA. “New super-advanced instrumentation will
revitalise the observatory. For example, Hubble’s new digital camera – The
new Advanced Camera for Surveys, or ACS – can take images of twice the
area of the sky and with five times the sensitivity of Hubble’s previous
instruments, therefore increasing by ten times Hubble’s discovery
capability! The European astronomers look forward to use the new camera
and perform new science building on the great breakthroughs they have
already achieved.”

ACS is going to replace the Faint Object Camera, or FOC, built by ESA.
The FOC, which has functioned perfectly since the beginning, has been a
key instrument to get the best out of the unprecedented imaging capability
of Hubble. The FOC was a “state-of-the art” instrument in the 80s, but the
field of digital imaging has progressed so much in the past 20 years that,
having fulfilled its scientific goals, this ESA flagship on Hubble is
chivalrously giving way to newer technology.

However, the story of FOC is not over yet: experts will still learn from
it, as it will be brought back to Earth and inspected, to study the
effects on the hardware of the long duration exposure in space.

Hubble is expected to continue to explore the sky during the next decade,
after which its work will be taken over by its successor, the powerful
ESA/NASA/CSA(*) Next Generation Space Telescope. NGST’s main focus will
be observations of the faint infrared light from the first stars and
galaxies in the Universe.

Notes for editors

The Hubble Space Telescope is a project of international co-operation
between ESA and NASA. It was launched in 1990. The partnership agreement
between ESA and NASA was signed on 7 October 1977; as a result of this
agreement European astronomers have guaranteed access to more than 20% of
Hubble’s observing time.

Astronauts have already paid visits to Hubble in 1993, ’97, ’99 and now,
in the spring of 2002, it is time for the fourth Servicing Mission (named
Servicing Mission 3B), planned for launch on 28th February. Originally
planned as one mission, the third Servicing Mission was split into two
parts (Servicing Mission 3A and 3B) because of the sheer number of tasks
to be carried out and the urgency with which Hubble’s gyroscopes had to be
replaced in late ’99.

In addition to the new solar panels and the ACS camera, astronauts will
install a very high-tech cooling system for Hubble’s infrared camera,
NICMOS. NICMOS has been dormant since 1999 when it ran out of coolant. The
new cooling system is a mechanical cooler, and works like an advanced
refrigerator.

Servicing Mission 3B will also include other maintenance tasks.
Altogether five extensive space walks are planned.

(*) CSA: Canadian Space Agency

For more information please contact

ESA – Communication Department

Media Relations Office

Paris, France

Tel: +33(0)1-53-69.7155

Fax: +33(0)1-53-69-7690

Ton Linssen, ESA HST Project Manager

Head of Management Support Office – Directorate of Science

Estec, Noordwijk – The Netherlands

Tel: +31-71-565-3477

Email: Antonius.Linssen@esa.int

Piero Benvenuti, ESA HST Project Scientist

Head of Space Telescope-European Coordinating Facility

Garching, Germany

Phone: +49-(0)89-3200-6291

E-mail: pbenvenu@eso.org

Lars Lindberg Christensen

Public outreach scientist,

Hubble European Space Agency Information Centre

Garching, Germany

Phone: +49-(0)89-3200-6306

Cellular (24 hr): +49-(0)173-38-72-621

E-mail: lars@eso.org

For more information on the Hubble Space Telescope visit the ESA Science
Website at: http://hubble.esa.int.

More information on the ESA Science Programme can be found at:
http://sci.esa.int. Info on ESA in general can be found at
http://www.esa.int