Researchers have found a candidate for the hypothetical Planet Nine, which could be an undiscovered giant planet way out in ...

Our solar system may have a ninth planet after all, following the declassification of Pluto nearly two decades ago, ...

Earth has four seasons, but do other planets in our solar system also have hot summer days and cold winter nights?

If the object really is Planet Nine, it would be larger than Neptune and exist 700 times further from the sun than Earth.

An international team including astronomers from the Center for Astrophysics | Harvard & Smithsonian (CfA) has announced the ...

Discovered in 1930, Pluto was long considered our Solar System's ninth planet, but was unseated in 2006 after the discovery ...

An alternate explanation that fits the evidence is that Vesta was once part of a planet – but which planet that might been ...

A 9th planet in our solar system might be found — and no, it’s not Pluto - Is there another planet out there? Researchers say ...

For years, astronomers have toyed with the idea that the Sun hides an extra planet so distant and dim that even the best ...

It takes between 10,000 and 20,000 years to orbit the sun. Some experts remain unconvinced about this discovery. It’s been almost two decades since our solar system lost its 9th planet.

This significant difference is primarily due ... Sun and orbits 67 million miles away from the sun. But it's the hottest planet in the solar system. But why? It has to do with Venus' atmosphere ...