The Gaia mission: Science, organization and present status

Research output: Contribution to journalArticle


The ESA space astrometry mission Gaia will measure the positions, parallaxes and proper motions of the 1 billion brightest stars on the sky. Expected accuracies are in the 725 as range down to 15 mag and sub-mas accuracies at the faint limit (20 mag). The astrometric data are complemented by low-resolution spectrophotometric data in the 3301000 nm wavelength range and, for the brighter stars, radial velocity measurements. The scientific case covers an extremely wide range of topics in galactic and stellar astrophysics, solar system and exoplanet science, as well as the establishment of a very accurate, dense and faint optical reference frame. With a planned launch around 2012 and an (extended) operational lifetime of 6 years, final results are expected around 2021. We give a brief overview of the science goals of Gaia, the overall project organisation, expected performance, and some key technical features and challenges.


  • L. Lindegren
  • C. Babusiaux
  • C. Bailer-Jones
  • U. Bastian
  • A. G A Brown
  • M. Cropper
  • E. Høg
  • C. Jordi
  • D. Katz
  • F. Van Leeuwen
  • X. Luri
  • F. Mignard
  • J. H J De Bruijne
  • T. Prusti
External organisations
  • Paris Observatory
  • Max Planck Institute for Astronomy
  • Leiden University
  • Royal Free Hospital
  • University of Barcelona
  • The French National Centre for Scientific Research (CNRS)
  • European Space Research and Technology Centre (ESA/ESTEC)
  • Heidelberg University
  • University of Copenhagen
  • University of Cambridge
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Astronomy, Astrophysics and Cosmology


  • Astrometry, Galaxy: kinematics and dynamics, Planetary systems, Relativity, Space vehicles, Stars: fundamental parameters, Techniques: photometric, Techniques: radial velocities
Original languageEnglish
Pages (from-to)217-223
Number of pages7
JournalProceedings of the International Astronomical Union
Issue numberS248
Publication statusPublished - 2007 Oct
Publication categoryResearch