About 100 European scientists are gathering in ESTEC over the next two days
to consider plans for the scientific organisation of Gaia — ESA’s ambitious
mission to help unravel the origin and evolution of our Galaxy. Experts in
general relativity, extra-solar planets, and a whole host of other relevant
disciplines are coming together to pool their knowledge about how Gaia can
best be organised.

Gaia was accepted as one of the next cornerstones missions of the ESA science
programme in October 2000. It is an ambitious experiment to map the positions
of about one billion stars in our Galaxy, providing an enormous advance in
the knowledge of our Galaxy’s structure and composition, and its origin and

ESA established its world leadership in this field of space science through
the Hipparcos star mapping satellite, operated between 1989-1993; Gaia will
improve on the Hipparcos results by a colossal three orders of magnitude
(factor of 1000) improvement in accuracy, and four orders of magnitude
(factor of 10000) in the total number of stars observed.

Through its five-year sky scanning, Gaia will compile an unprecedented census
of our Solar System, our Galaxy, and beyond: it will detect new Solar System
objects including near-Earth asteroids, tens of thousands of extra-solar
planets, hundreds of millions of variable and binary stars, and hundreds of
thousands of supernovae. The ESTEC meeting is the first step towards
finalising the satellite design, designing the complex data analysis system,
and preparing the diverse package of computer programmes necessary to analyse
the mass of data that the Gaia satellite will send to Earth after its launch
about a decade from now. Experts from a diverse range of disciplines are
contributing to these preparations for Gaia.

Gaia project scientist Michael Perryman has no doubt that ESA and the
European scientific community can deliver what the recently completed Concept
and Technology Study has claimed, and sees a sound organisation of the
scientific effort as an essential element of the mission’s success. “There
is a lot of excitement about Gaia’s expected scientific impact, our
scientific collaborators are pushing hard for ESA to get moving with this
programme, and everyone is just hoping that the Science Programme Committee’s
directive of a launch not later than 2012 will mean exactly that.”

The impressive line-up of European astronomers participating in this week’s
ESTEC meeting certainly provides confirmation of the interest and excitement
that the Gaia mission is generating within the European scientific community.


* Gaia home page (astrophysics division, SSD)


* Gaia home page



[Image 1:
Gaia — an ESA cornerstone mission — will build on the success of Hipparcos
and Europe’s expertise in astrometry.

[Image 2:
Gaia was adopted within the scientific programme of the European Space Agency
(ESA) in October 2000. It aims to measure the positions of an extremely large
number of stars with unprecedented accuracy. As a result, the distances and
motions of the stars in our Galaxy will be determined with extraordinary
precision, allowing astronomers to determine our Galaxy’s three-dimensional
structure, space velocities of its constituent stars and, from these data,
further our understanding of our Galaxy’s origin and evolution.