There have been questions about a mysterious ninth planet in our solar system for nearly a decade. Pluto was unseated as number nine in 2006. Now, a group of international researchers say they may ...

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 ...

With the same data but a different statistical analysis, researchers have spotted two additional planets in a system that was already thought to host seven of them, giving it one more planet than our ...

A leading scientist has told Newsweek about new evidence supporting the existence of a secret ninth planet lurking at the edge of our solar system. This hypothetical extra planet, often referred to as ...

An artist’s rendering of the theorized Planet Nine, back towards the sun. The planet is thought to be gaseous, similar to Uranus and Neptune. Hypothetical lightning lights up the night side. We get a ...

In 2006, updated research led to Pluto being controversially demoted to dwarf planet status by the International Astronomical Union. The reasoning was that Pluto's location in the far-flung ...

Caltech professor Mike Brown (L) and assistant professor Konstanin Batygin have been working together to investigate distant objects in our solar system for more than a year and a half. The two ...

For years, astronomers have been searching for a ninth planet in our solar system (after giving Pluto the old heave-ho and demoting it to a dwarf planet) and now researchers say they've found a ...

When I was a kid, the solar system was simple. There were nine planets and they all orbited in more-or-less circles around the sun. This same sun-and-a-handful-of-planets scheme repeated itself again ...

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