The NASA/ESA/ASI Cassini Huygens mission to Saturn, which has already
delivered stunning images and data of the ringed planet following
insertion into the Saturnian system on 1st July this year, is poised to
enter a crucial stage in its voyage of scientific discovery. In the
early hours of Christmas morning [25th December] the Huygens probe will
separate from the orbiter, its home for the last seven years, to
parachute down through the nitrogen-rich atmosphere of Saturn’s
largest moon, Titan, where it will come to rest – although the exact
nature of its final resting place remains a mystery. Scientists
speculate that Huygens may find lakes or even oceans of a mixture of
liquid ethane, methane and nitrogen.

Prof. John Zarnecki of the Open University, principal scientist for the
Science Surface Package, the first instruments to make contact with
Titan’s terra firma is open minded, “It’s a distinct possibility that I
could be the very first scientist to carry out oceanography on an outer
planet of the solar system.

But equally the probe could land with a thud on hard ground or squelch
into a morass of extraterrestrial slime – no one knows for sure. In any
event, the instruments onboard have been designed to handle a range of
possibilities. Let’s just say that after a seven year voyage and
twenty years of planning, design and build I will be extremely pleased
to land, whatever the surface”.

Following separation from the mothership Huygens will coast unguided
and unpowered for 20 days towards Titan where it will arrive on the 14th
January [2005] to begin its entry and descent to the moon’s surface.
Travelling at Mach 2 [1522 mph] the probe will enter Titan’s
atmosphere at an altitude of 1270km [789 miles] and decelerate to an
impact speed of 5 meters per second – the equivalent to jumping from a
chair onto the ground.

Commenting on the mission Prof. Ian Halliday, Chief Executive of the
Particle Physics and Astronomy Research Council [PPARC] that funds UK
involvement in the joint NASA/ESA/ASI project said, “Superlatives can
come easy when talking about space missions but this particular voyage
of scientific discovery is truly awesome. Huygens will be the furthest
man-made object to land on a remote celestial body and whilst the
science returns from Titan are eagerly awaited we shouldn’t forget
that the European Huygens probe is totally controlled by UK developed
systems and hardware. At a distance of almost 1.3 billion km [789
million miles] that’s quite a feat”.

Prof. Halliday added,” Titan is a mysterious place and raises many
scientific questions. Its thick atmosphere is mostly nitrogen, but there
are also methane and many other organic compounds. Some of them would be
signs of life if they were on our planet. Organic compounds form when
sunlight destroys methane. If sunlight is continuously destroying
methane on Titan, how is methane getting into the atmosphere?”

Notes for Editors

A Mission timeline, outlining critical steps is available at

A Media programme outlining briefings and data releases is at

Images to accompany this release are at and on the NASA/ESA
websites – see below for details.

Media Contacts

Peter Barratt – PPARC Press Office
Tel: 01793 442025. Mobile: 0787 9602899

Gill Ormrod – PPARC Press Office
Tel: 01793 442012 Mobile: 0781 8013509.

Franco Bonacina – ESA Press Office
Tel: +31 1 5369 7155

Don Savage – NASA HQ Press Office
Tel: +1 202 358 1727

Carolina Martinez – JPL Press Office
Tel: +1 818 354 9382

UK Science and Industrial Involvement
Contacts – for UK science and industry are available at
UK scientists are playing significant roles in the Cassini Huygens
mission with involvement in 6 of the 12 instruments onboard the Cassini
orbiter and 2 of the 6 instruments on the Huygens probe. The UK has the
lead role in the magnetometer instrument on Cassini (Imperial College)
and the Surface Science Package on Huygens (Open University). UK industry
had developed many of the key systems for the Huygens probe, including the
flight software (LogicaCMG) and parachutes (Martin Baker). These mission
critical systems need to perform reliably in some of the most challenging
and remote environments ever attempted by a man made object. LogicaCMG
software onboard the probe will be responsible for deploying the
parachutes, separating the front and back shield with precise timings to
achieve the required descent profile; reducing the velocity of Huygens
before commencing the science experiments, and managing communications
back to Cassini.


The Cassini-Huygens mission is a cooperative project of NASA, the
European Space Agency [ESA] and the Italian Space Agency [ASI].

The Jet Propulsion Laboratory, a division of the California Institute of
Technology in Pasadena, manages the Cassini-Huygens mission for NASA’s
Science Mission Directorate, Washington, D.C. The Cassini orbiter and
its two onboard cameras were designed, developed and assembled at JPL.

The Particle Physics and Astronomy Research Council (PPARC) is the
UK’s strategic science investment agency. It funds research, education and
public understanding in four broad areas of science – particle physics,
astronomy, cosmology and space science.

PPARC is government funded and provides research grants and
studentships to scientists in British universities, gives researchers
access to world-class facilities and funds the UK membership of
international bodies such as the European Organisation for Nuclear
Research, CERN, the European Space Agency and the European Southern
Observatory. It also contributes money for the UK telescopes overseas on
La Palma, Hawaii, Australia and in Chile, the UK Astronomy Technology
Centre at the Royal Observatory, Edinburgh and the MERLIN/VLBI National