After a decade-long search, some scientists say a growing number of clues point to the existence of a hidden planet in the ...

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This hypothetical Neptune-sized planet would circle our Sun on a highly elongated path, far beyond Pluto. It could have a ...

Our solar system consists of Sun and celestial bodies bound to it by gravity, including planets, moons, asteroids, and comets ...

"Get a free What If Top 10 book when you sign up for our newsletter: Earth is the only life-supporting planet in our Solar ...

MIT researchers analyzed precious samples from the asteroid Ryugu, delivered to Earth by Japan’s Hayabusa2 mission. They looked for clues of an ancient magnetic field.

A ninth planet may exist beyond Neptune in the Kuiper Belt, a region populated by icy bodies that orbit the Sun.

A joint Hubble and James Webb Space Telescope (JWST) project to learn more about the dusty disk around the bright star Vega ...

A new study suggests that the planet’s icy interior and liquid ocean could be insulated with a three-to-six-mile-thick layer ...

Astronomers have been trying to find a new planet beyond the orbit of Neptune for several decades, but all to no avail. Its nickname is Planet Nine; supposing this planet exists, it could help explain ...

A recent study points to an exciting possibility: that Uranus's moon Miranda, located in the far reaches of our solar system, ...