Debate has raged for two decades over whether Pluto should be considered a planet. Some want President Trump to take action via executive order.

The discovery of another moon around Pluto is exciting news for planetary science, but it's also likely causing some anxiety for the team in charge of New Horizons, a spacecraft set to be the first ...

Discovered in 1930 at the Lowell Observatory, Pluto was demoted as a planet in 2006. Some want President Trump to take action ...

Pluto lost its planetary status in 2006. Nearly two decades later, people are still arguing about it — and now the argument has reached the White House. NASA Administrator Jared Isaacman told the ...

President Donald Trump and his NASA administrator are reviving the Pluto debate again — apparently at the urging of “Star ...

Finally, a family portrait of Pluto is beginning to emerge! For the first time ever, astronomers have captured two never-before-photographed moons orbiting Pluto. NASA's New Horizons spacecraft ...

Earth has a newly-discovered neighbor in the solar system. But the heavenly body – possibly a dwarf planet à la Pluto – isn't a frequent visitor. Located beyond Neptune, its extreme orbit ...

WASHINGTON (Reuters) -Astronomers using the Hubble Space Telescope have observed a white dwarf - a highly compact stellar ember - that appears to have gobbled up an icy world akin to the dwarf planet ...