Lecturer: Prof. Paul Groot Affiliation: Radboud University Abstract: The short time-scale transient universe is still very poorly explored but holds strong promises for breakthrough discoveries. The detection of gravitational wave counterparts and the optical identification of fast radio bursts are but two outstanding examples. In the lecture I will overview the results of our group at Radboud University to understand the population of gravitational wave emitters in our Universe, to understand the fast synoptic sky at optical wavelengths and two major, upcoming projects. The MeerLICHT optical telescope that will be twinned with the MeerKAT/ThunderKAT radio array to achieve the first ever 'always-on' optical- radio synoptic survey. MeerLICHT is the prototype of the BlackGEM telescopes and will become operational in Spring 2017. The aim of the BlackGEM array of telescopes is the detection of optical counterparts to gravitational wave counterparts. It will also produce a 'Sloan South', at 1" resolution down to 22nd magnitude in six optical bands, as well as fully chart the sub-hour variability of the night sky, with an array of initially 3, eventually 15, 65cm telescopes with a field of view of 2.7 square degrees each. BlackGEM will become operation in mid-2018 and be located at ESO La Silla. Additional details of the upcoming Astrophysics' seminars can be found on the following link. ‏האירוע הזה כולל שיחת וידאו ב-Google Hangouts. הצטרף: https://plus.google.com/hangouts/_/mail.huji.ac.il/astrophysics?hceid=bWFpbC5odWppLmFjLmlsX2c0czhydDlpcmhwZzRvdGNybWIzZGFqcjdvQGdyb3VwLmNhbGVuZGFyLmdvb2dsZS5jb20.4eoda2pnkikplqv55cfo5iciik&hs=121