A new dwarf planet, discovered beyond Neptune and described as Pluto's 'cousin,' could void the hypothesis of a Planet X in ...

A small team led by Sihao Cheng, Martin A. and Helen Chooljian Member in the Institute for Advanced Study's School of Natural ...

In a thrilling development that challenges long-held assumptions about the outer reaches of our solar system, astronomers ...

Pluto has become a beloved object in our solar system ever since the International Astronomical Union (IAU) reclassified it from a planet to a dwarf planet back in 2006 – a decision which has ...

Astronomers have announced the discovery of a new dwarf planet in our solar system, named 2017 OF201. Located far beyond ...

On May 21, the International Astronomical Union’s Minor Planet Center announced the discovery of 2017 OF 201, which, because ...

There’s a new frozen oddball orbiting the Sun, and it’s not your average space rock. It’s a planet—a minor one, to be ...

Still, Ceres remains a dwarf planet. Perhaps as it should, given Pluto's relegation to dwarf planet — Pluto is 14 times larger than Ceres. Both Ceres and Pluto are given this designation because ...

When the International Astronomical Union (IAU) demoted Pluto from a planet to a dwarf planet in 2006, it surprised a lot of people, including some scientists. Even many years later, some ...

Ouch. Now officially labeled a “dwarf planet,” Pluto may have lost its title, but not our affection. After all, who doesn’t love a comeback story waiting to happen? To find out how Pluto ...

Arizona in 1930 and was considered our ninth planet until 2006. The International Astronomical Union reclassified Pluto as a dwarf planet because it does not clear its orbit of other debris.

In this region, objects in space could cross any dwarf planet — and Pluto’s — orbit. Pluto also sits within a larger field of objects surrounding the solar system called the Kuiper Belt.