Hands-on at this exhibit

  • Control a real scientific telescope
  • Touch real spacecraft components
  • Play an interactive game to launch stars through a milky way and see where they go
  • Use Gaia Touch! an interactive screen to explore the Gaia mission



Further reading

McMillan, P.J. & Binney, J.J. 2013 Analysing surveys of our Galaxy -- II. Determining the potential. Monthly Notices of the Royal Astronomical Society 433, 1411-1424

Hodgkin, S.T. et al. 2012 Transient astronomy with the Gaia satellite. Philosophical Transactions of the Royal Society A 371, 20120239-20120239

Perryman, M.A.C. et al. 2001 GAIA: Composition, formation and evolution of the Galaxy. Astronomy and Astrophysics 369, 339-363

At the end of 2013 a satellite was sent into orbit 1.5 million km from Earth, far beyond the moon's orbit. This satellite, Gaia, is tracking one billion stars as they move across the sky, and determining each star's distance, velocity, age and chemical composition. From these data we will map the distribution of the still mysterious dark matter that holds our Milky Way galaxy together, and gain vital clues as to how our galaxy was assembled.

At the end of 2013 a satellite, Gaia, was sent into orbit 1.5 million km from Earth. Discover how measuring the tracks of a billion stars across the sky with incredible precision will enable Gaia to chart a three-dimensional map of our Galaxy.

Stars appear to shift their positions on the sky every six months as the Earth moves around the Sun, with the magnitude of the shifts being inversely proportional to that star’s distance. A star that's moving with respect to the Sun also drifts across the sky. So, by precisely measuring the tracks of stars across the sky Gaia will determine the distances and the velocities of a billion stars.

Gaia will also measure with great precision the brightnesses and colours of those stars. From this data we can determine each star's mass, age and chemical composition. By modelling the motions of stars we will be able to map the distribution of the mysterious dark matter that holds galaxies together.  The distribution in space and velocity of different types of star will provide crucial clues as to how our galaxy was, and continues to be, assembled.

Lead image: The Gaia Satellite, the billion star surveyor, mapping the stars of the Milky Way.