Add Yahoo as a preferred source to see more of our stories on Google. Guests visting the Lowell Observatory in Flagstaff, Arizona during the I Heart Pluto Festival gaze at celestial objects from the ...

Swipe Down for Full Video Story Most of us learned that the Solar System has eight planets. For many years, Pluto made it ...

WASHINGTON — At a U.S. Senate committee hearing this week, NASA Administrator Jared Isaacman said that he believes Pluto should be classified again as a planet — a distinction that was removed from ...

After nine years and a journey of 4.8 billion kilometres, NASA's New Horizons robotic probe awoke from hibernation on Saturday to begin an unprecedented mission to study the icy dwarf planet Pluto and ...