Gaia

Gaia is a mission by the European Space Agency (ESA) to make a very detailed map of the stars and galaxies in our Milky Way. Its goal is to chart more than 1 billion stars and galaxies and observe them in three dimensions over a period of 5 years. It will also measure the positions and distances of stars, their proper motions, and the amount of light they emit. This will help scientists understand the structure, formation, and evolution of our galaxy.