Technical Description of Galaxy-Mapping Gaia Telescope - ESA

INSIDE GAIA'S BILLION-PIXEL CAMERA (FOCAL PLANE)

Gaia's payload carries two identical telescopes, pointing in two directions separated by a 106.5° basic angle and merged into a common path at the exit pupil. Three instruments detect the light collected by these telescopes.

ESA's Gaia mission will produce an unprecedented 3D map of our Galaxy by mapping, with exquisite precision, the position and motion of a billion stars.