Por André Moitinho (DF-FCUL).

Abstract: Gaia is a cornerstone mission of the European Space Agency (ESA) launched in December 19, 2013. Its main scientific goal is to understand the structure and development of our Galaxy, the Milky Way. The originality of Gaia lies on its unprecedented ability to determine stellar positions with micro-arcsecond accuracy. With this accuracy, astronomical distances in the Milky Way and beyond will be geometrically determined through parallaxes, providing solid fundamental steps of the Cosmological distance ladder reaching at least as far as the Magellanic Clouds. But Gaia will provide much more. It is gradually producing a Petabyte-scale data archive for almost two billion sources. The archive includes space motions, photometry, time series,  and astrophysical parameters, which are fundamental observables for research done at CENTRA: Galactic structure, stellar physics, General Relativity tests, distance-scale and age of the Universe, dark matter mapping, celestial reference frame, supernovae, quasars. Gaia Data Release 1 (GDR1) was issued in 2016. It was a test release containing parallaxes and proper motions for only 2.5 million sources. Still, the mission's scientific impact is already considerable. The second data release will happen in April 25, 2018, it will contain parallaxes and proper motions of over a billion sources and is expected to alter dramatically our current ideas on several fields of astrophysical research. In this talk I will give an overview of the mission, present results from GDR1 and discuss the scientific potential of the upcoming data releases.