Gaia DR2 and Serbian-Bulgarian investigations

Abstract

On April $25^{th}$ 2018, the second release of the Gaia catalog (DR2) appeared. It is based on 640 days of Gaia satellite observations; GAIA means Global Astrometric Interferometer for Astrophysics. The observing period was August $22^{nd}$ 2014 - May $23^{rd}$ 2016 (1.75 yr or 21 months with some interruptions). The reference epoch is J2015.5 . The positions and proper motions refer to the ICRF. The DR2 is publicly available in the online Gaia Archive (https://archives.esac.esa.int/gaia). After Hipparcos, it is the cornerstone mission of the European Space Agency (ESA). The next solution (DR3) is planed for the first half of 2021. The main results of DR2 with Serbian-Bulgarian investigations about it are presented.