31 Jan 2000 Press conference 4 February

The stars are the chemical factories of the Universe: they synthesise
in their cores new chemical elements that combine in the stellar
outskirts to produce new molecules, and these will become part of
the raw material out of which more stars, planets, and maybe even
living organisms will form. ESA’s infrared space telescope, ISO, has
identified many of these compounds in space.

About 150 astronomers, including many experts in space-chemistry,
will present and discuss results in the field at ESA’s Villafranca
station, in Madrid, Spain, from 2 to 4 February.

Leading topics will be:

the confirmation by
ISO of the true
nature of the large
organic molecules found in many space environments;
the opening of a whole new field of ‘astro-mineralogy’;
the role of the water molecule in space;
and the origin of different bodies in our own Solar System.

Most molecules emit the bulk of their energy in the form of infrared
light, and most infrared light is unable to cross the Earth’s
atmosphere. ISO is therefore the first telescope that has been able
to make a detailed analysis of the space chemistry. The two
spectrometers on board ISO could detect with a good resolution the
‘chemical fingerprint’ of many molecules. For instance, one of the
main ISO results in this field has been the detection of the molecule
of water in many regions of space – from clouds where new stars are
forming, like Orion, to the centre of our galaxy. And ISO also studied
the composition of several planets and comets in the Solar System,
which allowed the scientists to test the models about their formation.

During the workshop ‘ISO beyond the peaks’ at ESA’s Villafranca
station in Madrid (2-4 February), astronomers will present new results
related to the presence in space of the molecules PAHs (Polycyclic
Aromatic Hydrocarbons), whose true nature has been under
discussion for two decades. ISO’s new data will help to solve the
problem.

The fact that these compounds are so abundant shows that a very
rich and active organic chemistry takes place in the space among
the stars. Links between this chemistry and the chemistry developed
in new-born planetary systems, including our own Solar System, are
actively searched in comets and meteorites. Such studies may yield
a clue on the problem of the origin of life in our Universe, as complex
carbon-containing molecules are considered by some as pre-biotic
material.

Other results to be presented have to do with the composition of the
dust around stars. ISO has detected crystals in this dust for the first
time, which allows a totally new field to open up: ‘astro-mineralogy’.
By the identification of each crystal astronomers will now be able to
track their presence in different environments, and this will provide
many clues about how the universe evolves.

**A press conference will be held on 4 February, 13.00 hours, at
ESA’s Villafranca station, Madrid.

Scientists attending the press conference:

Alberto Salama (ESA, ISO Data Centre), Chairman

José Cernicharo (CSIC)

Christine Joblin (CESR, Toulouse)

Rens Waters (University of Amsterdam)

Martin Kessler (ESA, ISO project scientist)

Journalists wishing to attend please send an email to:

msalomon@iso.vilspa.esa.es

or phone +34 918131280 or +34 649 934887