Thank you for reading and commenting, Joris! We kind of do spam signals out there, since our old radio and TV signals have been emanating outward for the past 100+ years. The focused, more powerful signals are better, but it costs a lot of money. The Arecibo signal sent in 1974 was the first intentional one sent into space. METI sent a signal aimed at the potentially habitable exoplanet GJ 273b around Luyten’s Star 12 light years away back in November of 2017.