WASHINGTON (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, spotting it as it ...

Ever since the first explorers charted the outer reaches of our Solar System, its true boundaries have remained hazy. While the Voyager probes have gone far into interstellar space, our Sun’s ...

Add Yahoo as a preferred source to see more of our stories on Google. An illustration showing Planet Nine, a hypothetical, undiscovered planet in our solar system. New research now suggests the ...

Astronomers have discovered a new member of a rare and mysterious class of solar system objects known as sednoids — a subset of extreme trans-Neptunian objects (ETNOs) with exceptionally distant, ...

Forbes contributors publish independent expert analyses and insights. An award-winning reporter writing about stargazing and the night sky. Astronomers have found a distant celestial body — ...

A possible new dwarf planet has been discovered at the edge of our solar system, so far-flung that it takes around 25,000 years to complete one orbit around the sun. The object, known as 2017 OF201, ...

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 ...