PASADENA, Calif.–The International Astronomical Union (IAU) today downgraded the status of Pluto to that of a “dwarf planet,” a designation that will also be applied to the spherical body discovered ...

Is a sun a star or a planet? While science now agrees the sun is a star, new telescopes may soon challenge how we define ...

In the cold, distant reaches of the Solar System, far beyond Pluto, astronomers have just identified what could be a new dwarf planet. It's called 2017 OF 201, a rock that appears to be some 700 ...

WASHINGTON >> Scientists have identified an object about 435 miles wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet, spotting it as it travels on a ...

Beyond the familiar planets lies a fascinating frontier filled with icy worlds, mysterious orbits, and cosmic curiosities. These are the dwarf planets—small but mighty members of our solar system that ...

A team of astronomers believe they may have discovered a new dwarf planet—just like Pluto—on the edge of our solar system. The object—which orbits out beyond Neptune—has been named "2017 OF201" by the ...

What can white dwarf stars eating their own planets teach astronomers about planetary and solar system formation and ...

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 ...

Ten observatories in six European countries teamed up for recent observations of a stellar occultation by the dwarf planet Haumea, which surprisingly show a narrow and dense ring orbiting the dwarf ...

Pluto, the most famous dwarf planet, lost its planet status in 2006. Learn more about dwarf planets of the solar system here. NASA's Dawn spacecraft has been granted a mission extension that will ...