ガイア
ESA astrometry mission whose science observations ended on 15 January 2025 after mapping positions and motions of billions of stars.
概要
ESA's Gaia mission measured positions, parallaxes and proper motions of nearly two billion stars from L2. Its astrometric catalogue produced the most precise three-dimensional map of the Milky Way ever assembled.
主な発見
- Parallaxes for roughly 1.8 billion stars
- Discovery of ancient merger debris in the Milky Way
- A precise anchor for the local cosmic distance ladder