Journey beyond Neptune to uncover the frozen, mysterious worlds that challenge everything we thought we knew about the solar ...

On a chilly morning in February 1930, a young astronomer named Clyde Tombaugh was hunched over a blinking comparator at the Lowell Observatory in Arizona, studying pairs of photographic plates of the ...

NASA has released new images of Pluto’s far side, a region never before captured in high resolution. Taken by the New Horizons spacecraft as it sped away from the dwarf planet, the photos reveal icy ...