Add Yahoo as a preferred source to see more of our stories on Google. Earth has a newly-discovered neighbor in the solar system. But the heavenly body – possibly a dwarf planet à la Pluto – isn't a ...

Two decades ago, the International Astronomical Union—which defines and names celestial bodies—redefined the criteria for being a planet, putting Pluto into the new category of dwarf planet ...

Pluto is a bit of a loner. The dwarf planet is no longer considered a regular planet; it does not orbit on the same plane as the solar system's eight planets; and its orbit is both highly elliptical ...

Current NASA head Jared Isaacman, himself something of a controversial choice, is determined to get Pluto reclassified as a ...

He also said that NASA is working on research papers that they would like to bring forward within the scientific community to revisit the discussion.

There’s been a fierce debate over the past two decades about the status of the distant icy world of Pluto after it was contentiously stripped of its planethood and reclassified as a dwarf planet. Nasa ...

NASA chief Jared Isaacman’s call to restore Pluto’s planetary status has reignited a long-running scientific debate over ...

It's been 20 years since Pluto lost its status as the ninth planet of the solar system, but we still can't seem to let it go.

Is Pluto a planet? NASA Administrator Jared Isaacman told Congress on Tuesday that Pluto should be recognized as a planet, 20 years after its status changed.

This close up look at Pluto and Charon, taken as part of the mission's latest optical navigation ("OpNav") campaign from Jan. 25-31, 2015, comes from the Long Range Reconnaissance Imager (LORRI) on ...