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.

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

A mysterious new world may be hiding in the outer reaches of our solar system. According to arecent study published on arXiv ...

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

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

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

New discoveries of objects in the Kuiper Belt have also presented challenges for the Planet Nine theory. The latest is known ...

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

According to the paper laying out the research behind the discovery, "TOI-1846b is a super-Earth-sized planet, with a radius of approximately 1.8R⊕, placing it within the intriguing radius valley area ...

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 ...

When Scientific American published its very first issue 180 years ago this month, our view of the cosmos was substantively different. Closer to home, astronomers were wildly guessing about how our ...