When I was a kid, there were nine planets. Now we know of thousands! But that includes exoplanets, alien worlds that orbit alien suns.Only eight planets call our solar system home. Or there might ...

A possible dwarf planet, like Pluto, has been observed in our solar system, according to a preprint published in arXiv. The area of space where this planet was found was previously thought empty.

When it was discovered in 2005, suddenly it became clear that the Solar System couldn’t keep having nine planets. Something was going to change. What makes a dwarf planet?

A potential dwarf planet has been discovered in the outer reaches of our solar system, orbiting beyond Neptune. Its presence there challenges the existence of a hypothetical body known as Planet 9 ...

Pluto was reclassified as a dwarf planet in 2006. Our solar system may have a ninth planet after all, researchers say. The possibility that an additional planet may be hidden far into the solar ...

Our solar system – which includes the Sun, eight planets, five dwarf planets, hundreds of moons and millions of asteroids, comets, and meteoroids – has been the centre of studies covering a ...

WASHINGTON, May 30 (Reuters) - Scientists have identified an object about 435 miles (700 km) wide inhabiting the frigid outer reaches of our solar system that might qualify as a dwarf planet ...

This new dwarf planet may exist at the edge of the solar system, possibly disproving Planet Nine's existence. This is the story of that newly encountered planet.

An object eight times the mass of Jupiter may have swooped around the sun, coming superclose to Mars' present-day orbit before shoving four of the solar system's planets onto a different course.

Earth has a newly-discovered neighbor in the solar system.. But the heavenly body – possibly a dwarf planet à la Pluto – isn't a frequent visitor. Located beyond Neptune, its extreme orbit ...

The dwarf planet candidate’s closest point to the sun is about 7 billion kilometers, roughly 45 times that of Earth’s distance. One trip around the sun takes more than 24,000 years.