September - First image of a black hole

You can pre-order the calendar from the ESOshop. Deliveries will start in the second half of November 2019. 

The Event Horizon Telescope (EHT) — a planetscale array of eight ground-based radio facilities forged through international collaboration — has been designed to capture images of black holes at the centres of galaxies. In coordinated press conferences across the globe, EHT researchers revealed that they succeeded, unveiling the first direct visual evidence of the shadow of a supermassive black hole in the centre of the galaxy Messier 87.

Although the constituent telescopes of the EHT are not physically connected, they are able to synchronise their data precisely using atomic clocks — hydrogen masers. The observations for this result were collected at a wavelength of 1.3 mm during a 2017 global campaign. Each telescope of the EHT produced enormous amounts of data — roughly 350 terabytes per day — which were stored on highperformance helium-filled hard drives. These data were flown to highly specialised supercomputers — known as correlators — at the Max Planck Institute for Radio Astronomy and the Massachusetts Institute of Technology Haystack Observatory to be combined. They were then painstakingly converted into an image using computational tools developed by the collaboration.