Rather than a vast ocean, Pluto’s heart might be hiding a huge, heavy treasure. Computer simulations suggest that an object about 730 kilometers wide, slightly larger than the asteroid Vesta, could ...

The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the International Astronomical Union (IAU). Recent discussions and new scientific ...

Capping years of intense debate, astronomers resolved Thursday to demote Pluto in a wholesale redefinition of planethood that is being billed as a victory of scientific reasoning over historic and ...