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Everything You Always Wanted To Know About Gaia!


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Following the success of Hipparcos, ESA is planning to launch a much more powerful astrometric satellite called Gaia. Gaia will use the most advanced technology to create an extremely precise dynamic three-dimensional map of our Galaxy with positions, distances and also velocities of more than 1000 million stars. Its accuracy will be 20 microarcseconds for faint stars (equivalent to measuring the diameter of a human hair at a distance of 1000 km!) and even better for brighter stars.

Positional Accuracy Through History

The science case for Gaia is extremely broad and ambitious and its ultimate aim is to solve one of the most challenging yet fundamental questions of modern science: understanding the origin and evolution of our own Galaxy, the Milky Way. It will also revolutionise the search for extrasolar planets by detecting thousands of them in the solar neighbourhood.

Gaia represents the dream of many generations as it will bring light to questions that astronomers have been trying to answer for many centuries. It is the expression of a widespread curiosity about the nature of the Universe combined with the most cutting-edge technologies developed by creative engineers.

Click on the thumbnail below to see how the accuracy of our measurements has improved through history:

Positional Accuracy


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