A new analysis of planet formation models estimates the odds of a theoretical Planet Nine orbiting our sun at 40% given ...

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

There’s a new object in the distant reaches of our solar system, and it might just offer clues to a long-standing cosmic ...

The newly discovered object, named 2017 OF201, has a 25,000-year orbit and is believed to be a large contender for dwarf ...

The International Astronomical Union’s Minor Planet Center, which catalogs new moons and other small bodies in the solar ...

Now, a newly identified object spotted in two infrared sky surveys has renewed the question of whether the elusive and hypothetical Planet 9 actually exists. According to a new pre-print study ...

The argument for the planet has to do with the Kuiper Belt: a region of icy debris far beyond Neptune’s orbit. The hypothetical planet would explain some strange orbits of the objects there.

Based on density considerations, the team estimates that the planet is a water world, a class of hypothetical planets covered in a deep ocean with an atmosphere rich in water vapor (such as the ...

From city commutes to mountain hikes, these top backpack brands craft companions that are as resilient as they are stylish, ...

an illustration showing the hypothetical Planet 9 with blue rings and a question mark over it, with stars and a galaxy in the background For decades, astronomers have noticed objects behaving ...

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