Might the solar system harbor not just one, but two unknown planets? A fresh study of the Kuiper Belt’s structure has revived ...

Astronomer used to think that the Kuiper Belt was a few hundred times larger than the Asteroid belt. They thought it was a donut shaped structure that started at Neptune and extended out 2 billion ...

A newly discovered warp in the outer Solar System may have been created by a small, rocky world, much closer to the Sun than ...

The search for an unknown planet in our solar system has inspired astronomers for more than a century. Now, a recent study suggests a potential new candidate, which the paper’s authors have dubbed ...

Japanese researchers have used computer simulation and the orbits of several large objects past Neptune to calculate that there is Kuiper Belt planet (KBP) 1.5–3 times as massive as Earth, located at ...

Discovery of 2017OF201, a large trans-Neptune Object, challenges previous beliefs about the Kuiper Belt and hints at the ...

On August 24, 2006, our solar system lost a planet. It wasn't by cataclysmic destruction, but rather by the vote of the International Astronomical Union, which declared that Pluto, considered the ...

It is a question that feels like it should have a straightforward answer: how many planets are there in our solar system? Since Pluto was relegated back down to dwarf planet status, almost everyone ...

The discovery of Quaoar, a magnitude 18.5 object located in the constellation Ophiuchus, was announced on October 7, 2002, at a meeting of the American Astronomical Society. The earliest prediscovery ...

The cold and shadowy fringe of the solar system known as the Kuiper belt is generating increasing debate among scientists as data accumulates on the growing population of objects discovered there. Now ...