Four billion miles from Earth, the New Horizons probe that recently sent such lovely pictures of Pluto is drawing near to the most distant object mankind has ever come close to: Ultima Thule, a mysterious rock deep in the Kuiper belt. The historic rendezvous takes place early tomorrow morning.
This is an encounter nearly 30 years in the making, if you count back to the mission’s beginnings in 1989, but it’s also been some 13 years since launch — the timing and nature of which was calculated to give the probe this opportunity after it had completed its primary mission.
New Horizons arrived at Pluto in the summer of 2015, and in its fleeting passage took thousands of photos and readings that scientists are still poring over. It taught us many things about the distant dwarf planet, but by the time it took its extraordinary parting shots of Pluto’s atmosphere, the team was already thinking about its next destination.
Given the craft’s extreme speed and the incredibly distant setting for its first mission, the options for what to investigate were limited — if you can call the billions of objects floating in the Kuiper Belt “limited.”
In fact the next destination had been chosen during a search undertaken in concert with the Hubble Space Telescope team back in 2014.