Free Astronomy Magazine July-August 2019

41 JULY-AUGUST 2019 SPACE CHRONICLES than 1700 scien- tific publications since its launch in 2013. In order to reach the accuracy neces- sary for Gaia’s sky maps, it is crucial to pinpoint the position of the space- craft f r om E a r t h . Therefore, while Gaia scans the sky, gathering data for its stellar cen- sus, astronomers regularly monitor its position using a global network of optical telescopes, in- cluding the VST at ESO’s Paranal Observatory. The VST is currently the largest survey telescope observing the sky in visible light, and records Gaia’s position in the sky every sec- ond night throughout the year. T his image shows Gaia's all-sky view of the Milky Way based on measurements of almost 1.7 billion stars. [ESA/Gaia/DPAC]