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

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

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 ...

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

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

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 ...

A recent study hints at a previously unknown Earth-sized planet, dubbed Planet Y, potentially influencing gravitational distortions in the outer solar system.

Hundreds of millions of years ago, an asteroid caught by Earth's gravity might have fragmented, creating a temporary ring ...