Video: New Horizons animation

NASA managers formally approved the New Horizons mission another speedy encounter with an object at the frontier of the solar system, but denied a request from scientists to redirect the Dawn spacecraft to visit a third destination in the asteroid belt, opting to keep it in orbit around the dwarf planet Ceres, officials said Friday.

The New Horizons spacecraft has captured its last view of mysterious dark blotches strung across Pluto’s equator, and the spots will likely keep scientists guessing about their origin for decades to come.

Data from the encounter of NASA’s New Horizons spacecraft with a frozen reddish snowman-shaped object a billion miles beyond Pluto last year suggest the building blocks of planets may have formed less violently than many scientists expected, officials said Thursday.