trans-neptunian objects

Planetary scientists suggest an Earth-like planet, no bigger than three times the Earth's mass, could lurk beyond the orbit of Neptune.

Planet 8.5

Have we finally cracked the code?

Scientists Say There May Be Another Earth-Sized Planet Lurking in the Solar System

A team of astronomers suggest trans-Neptunian objects could still be distributed uniformly in our Solar System, poking a hole in the Planet Nine theory.

Captain Planet

Did the scientists behind the Planet Nine hypothesis make an embarrassing mistake?

Planet Nine Might Not Actually Exist, Scientists Say

A team of astronomers at the UPenn have discovered 139 minor planets — too small for a planet, but not a comet either — orbiting the Sun past Neptune.

Pluto Not So Special Anymore

The search for Planet Nine just got a lot more interesting.

Scientists Discover 139 New "Minor Planets" in Our Solar System

The hunt is yielding more clues.

New Kid on the Block: “Extreme” Objects Found May Lead to Proof of Planet Nine

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