As most of America’s East Coast counts down toward midnight tonight, ushering in a shiny new year, a group of NASA scientists and their attendant press will instead be counting down to a more spectacular event: the most distant flyby of a planetary object in history.

After zipping past Pluto in 2015, snapping breathtaking photos and revolutionizing our understanding of the dwarf planet, the New Horizons probe has drifted farther and deeper into the solar system. Tonight, some billion mile