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 ...

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 ...

While the James Webb Space Telescope looks for the most distant galaxies ever seen, astronomers have discovered something new in our very own solar system. Researchers from the U.S. and Canada have ...

The planet Neptune wobbled in its orbit around the Sun. That could only mean one thing, astronomers said: There was a ninth planet out there, somewhere, lurking in the fringes of the solar system.

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 ...

A possible cousin of Pluto seems to be circling the far reaches of the solar system. The dwarf planet candidate 2017 OF201 travels in a superwide orbit, with the sun relatively near one end of its ...

At the very edge of our solar system, beyond the grasp of Neptune and even past the icy sprawl of Pluto’s domain, a new frozen world has emerged from the shadows. It’s not a new Earth or the mythical ...

On Aug. 24, 2006, the International Astronomical Union (IAU) decided that Pluto wasn't a planet anymore. Instead, Pluto is now officially classified as a dwarf planet along with four other confirmed ...

Several Johns Hopkins University astronomers described a decision Thursday to strip Pluto of its planetary status as a “muddled” ruling that is unlikely to settle ongoing debates over how to define a ...

It's not exactly news to say that Pluto is no longer considered a planet. That made headlines almost 20 years ago. But what if I told you that decision at the time was controversial, not just among ...