Go to start pageGalaxy StoryAstrometrySearch for Planets

What will I find?
This picture shows Hipparcos and Gaia - two satellites that identify objects in the Milky Way Galaxy. Click on the magnifying glass below to explore the difference between Hipparcos data gathered after 1989 and that projected for Gaia to be launched about 2011. Choose any of the stories listed on the left if you want to find out more about Astrometry.


Measuring the Milky Way

ESA Science Home page

See also:

Gaia Home page