Nasa may revisit one of outer space’s thorniest questions ...

Astronomers have discovered a brand-new class of exoplanet unlike anything previously known. This discovery, featured in ...

Frigid water helped paint Mars red and may have shaped a vast coastline, two new studies into the planet’s history reveal. Scientists have detected a possible ancient beach in Mars’ northern ...

Mike Brown is convinced that beyond Neptune, at the far reaches of our solar system, there's an unseen giant planet. "This is the 5th largest planet in our solar system, lurking out there, waiting to ...

A provocative new study suggests Dante’s Inferno may have secretly doubled as a giant cosmic impact scenario centuries before ...

Pluto was reclassified as a dwarf planet in 2006, but new discoveries and fresh debate are reigniting calls to restore its planet status. Learn why Pluto lost its title, what scientists discovered ...

Forbes contributors publish independent expert analyses and insights. Leslie Katz covers the intersection of culture, science and tech. A yellowish-orange glow bathes Phainoterra, a planet of dramatic ...

Six planets will align before dawn on June 3 in a planetary parade, but only two will be visible to the naked eye. Mercury, Jupiter, Uranus and Neptune will likely be obscured by the rising sun or ...

A possible cousin of Pluto seems to be circling the far reaches of the solar system. The dwarf planet candidate 2017 OF201 travels in a superwide orbit, with the sun relatively near one end of its ...