GAIA - The largest astronomical discovery machine in history

About the project

For decades people have been trying to explore the universe. GAIA, a space mission of the European Space Agency (ESA) launched in 2013 for the most xtensive survey of our galaxy to date.

With the GAIA space telescope, astronomers are able to take measurements of approximately one percent of all the stars in our Milky Way – an estimated one billion stars – with very high precision. Using these star measurements, researchers will create a three-dimensional map of the Milky Way. This map also contains the positions, distances and movements of the celestial bodies in space. These findings will help scientists clarify the origin of stars and the development of the Milky Way.

A representation capturing the GAIA ESA mission
©ESA/ATG medialab; background: ESO/S. Brunier

Our contribution

To perform such measurements requires highly sensitive cameras. A spectrometer records the light from the stars and determines whether the stars are moving towards or away from us. The spectrometer separates light according to color and also prevents spherical aberrations. To achieve this various optical components requires: a filter, two prisms, two prism lenses and a diffraction grating. All of these optical elements are made of the fused silica Suprasil from Heraeus Conamic.

Suprasil is a material with very good optical homogeneity as well as very high transmission (light transmittance) at high radiation exposure in space.

An image of a GAIA product by Heraeus
©EADS Astrium SAS, France