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

Almost 20 years after Pluto was infamously downgraded from its status as a planet, scientists now believe they have ...

Astronomers may be close to identifying a mysterious object in our solar system. New research points to a potential candidate ...

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

For instance, Neptune migrated outward, switching places with Uranus, and pushed a lot of the small, icy bodies into the ...

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

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet ... that could be a possible candidate as "Planet Nine," according to a new paper, which has been ...

The chance of a planet forming in the outer reaches of the solar system - a hypothetical Planet Nine - could be as high as 40 ...

Check out the rest of the series. If you were born in the last century you might have memorized that there were nine planets in our solar system, as heard in the famous Schoolhouse Rock!

When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns. Only eight planets call our solar system home. Or there might ...

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