On Jan. 15, 2025, the Gaia spacecraft took its last image. Then the craft ran a final round of engineering tests, fired its thrusters to leave Earth behind, and slipped into an orbit around the Sun, ...

Gaia was conceived as part of ESA's Horizon 2000+ campaign, a long-term development guide similar to the Decadal Survey used by American space research agencies. First proposed in 1993, Gaia was ...