This is why I always recommend to friends having Sat installed in their homes have an outlet installed in every room they think they might ever want a TV. Ideally, this would be all family/living rooms, all bedrooms, basement and kitchen. Garage too for those who like to watch TV while they work on stuff.
Unlike cable, it cannot simply be split. You have to have a multiswitch. And it has to be a powered multiswitch if you go 8 or higher.