NASA speeds toward historic flyby of faraway world, Ultima Thule

NASA counted down Monday to a historic flyby of the farthest, and quite possibly the oldest, cosmic body ever explored by humankind -- a tiny, distant world called Ultima Thule -- in the hopes of learning more about how planets took shape. The US space agency planned to ring in the New Year with a live online broadcast to mark the spacecraft's zoom past the mysterious object located about four billion miles (6.4 billion kilometers) away in a dark and frigid region of space known as the Kuiper Belt. The flyby at 12:33 am Tuesday (0533 GMT) will take place about a billion miles beyond Pluto, which was until now the most faraway world ever visited up close by a spacecraft.