Planet Nine was previously suggested as a possible explanation for distant orbital clustering. It was thought to be ten times Earth’s mass, orbiting far beyond Neptune.

The Solar System does not have a clear border. The influence of the Sun in certain domains is small enough for the Voyager ...

Astronomers propose a new hypothetical planet, Planet Y, beyond Neptune, based on observed orbital anomalies in the Kuiper ...

A study suggests an Earth-sized planet, dubbed Planet Y, may exist beyond Neptune, affecting the orbits of icy objects in the ...

A new study suggests the existence of Planet Y. This hidden planet may be affecting the Kuiper Belt. The gravity of Planet Y ...

Astronomers have picked up evidence of an Earth-sized world, distinct from the previously hypothesised Planet Nine and Planet ...

For astrobiologists, the search for life beyond our solar system could be likened to where one would look in a vast ...

Recent research suggests a warp in the orbital plane of Trans-Neptunian Objects (TNOs) between 80 and 400 AU, hinting at the ...

Neptunes, exoplanets whose sizes are between Earth and Neptune, and which are between the known for their water-rich ...

On August 24, 2006, Pluto ceased to be considered a planet. A mixture of rock and ice located in the Kuiper Belt, a region of icy objects beyond the orbit of Neptune. This demotion ...

You might be thinking about a giant trilobite found on Pluto, or maybe a dinosaur skeleton on the planet. However, when astronomers use the word "fossil" for ...

A new study on Uranus has found it is hotter than we thought, prompting scientists to suggest we should return to the ice ...