Gaia is on its way to map the Milky Way.
The ESA spacecraft blasted off at 4:12 a.m. EST on December 19 from Europe’s Spaceport in Kourou, French Guiana. It will travel about 1.5 million kilometers beyond Earth before settling into a stable orbit around the sun.
Once there, the spacecraft will spend five years recording the location, brightness and motion of 1 billion stars in the galaxy. Astronomers will use the data to make the most precise, three-dimensional map of the Milky Way to date.
Gaia is also expected to identify comets and asteroids inside the solar system, planets outside the solar system, failed and exploding stars and distant active galaxies called quasars.