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 ...

Across neuroscience, psychology and fringe physics, a provocative idea is gaining new language: that the human mind might be ...

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 ...

All of our solar system’s planets are lining up in the night sky at once this week. This extraordinary celestial event will see the sky scattered with seven visible planets in what is known as a great ...

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. When ...

Our solar system is a smashing success. A new study suggests that from its earliest period — even before the last of its nebular gas had been consumed — Earth’s solar system and its planets looked ...

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 ...

(CNN) — 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 ...

Planet Y is the latest in a series of hypothetical solar system planets that scientists have proposed in recent years, all with slightly different characteristics but collectively believed to be ...