For decades, our solar system was thought to have nine planets, with Pluto considered the smallest and farthest. But in 2006, ...

A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 ...

The small world was found during a search for the hypothetical Planet Nine, and astronomers say the next time it will reach ...

U.S. astronomers hunting for "Planet Nine" have instead stumbled on what appears to be a new dwarf planet in the solar system ...

Astronomers find evidence of a possible ninth planet beyond Neptune, reigniting the debate about the formation of the Solar ...

As a result of the International Astronomical Union’s 2006 demotion of Pluto from planet to dwarf planet, our solar system ...

Our solar system may have a ninth planet after all, researchers say ... body that could be a possible candidate as "Planet Nine," according to a new paper, which has been accepted for publication ...

Growing up, I was taught that there were nine planets in the solar system. That all changed in 2006, when the International Astronomical Union voted to demote Pluto’s status to that of dwarf planet.

In the cold, dark outskirts of planetary systems far beyond the reach of the known planets, mysterious gas giants and ...

The solar system has eight official planets: Mercury ... Although scientists remain divided over Planet Nine's existence, one thing they all agree on is that actually finding the elusive world ...

the nine images stitched to a panorama and a HDR blend of one of the frames to reveal Saturn, Neptune and Mercury. “These three planets not easy to see at all.” The alignment has happened ...

When I was a kid, there were nine planets. Now we know of thousands ... Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus, Neptune and Pluto all claimed that moniker. But then some pesky ...