There’s no Idea Channel episode this week, so instead enjoy a PBS Space Time YouTube episode instead! Everyone has their own opinion as to whether or not aliens exist. But let’s assume they do for a second and we wanted to let them know we’re here!!!! How should we signal our species’ existence through the expanse of space? There are a few options, but which is the most effective and the cheapest? Find out in this week’s episode of PBS Space Time!