Add Yahoo as a preferred source to see more of our stories on Google. This image of Pluto was made after the New Horizons spacecraft flew past the dwarf planet on July 14, 2015, from a distance of ...

Planetary years become dramatically longer the farther a world sits from the Sun, but some of the strangest effects go far ...

Pluto has long been one of the most controversial objects in our Solar System. For decades it proudly held the title of the ...

Add Yahoo as a preferred source to see more of our stories on Google. Earth has a newly-discovered neighbor in the solar system. But the heavenly body – possibly a dwarf planet à la Pluto – isn't a ...

Pluto’s atmosphere may finally be thinning as it moves farther from the sun, with observations suggesting atmospheric pressure has fallen by as much as 16%.

It is hard to believe that 20 years ago, on Aug. 24, 2006, our beloved Pluto was reclassified as a dwarf planet. Pluto ...

For the first time since its discovery in 1920, Pluto is entering the outer solar system—a journey that’s slowly thinning out its atmosphere. Reading time 3 minutes Pluto’s orbit around the Sun is a ...

For decades, scientists and the general public have argued over the astronomical status of beloved dwarf planet Pluto. In the latest salvo, NASA Administrator Jared Isaacman said that he was “very ...

James is a published author with multiple pop-history and science books to his name. He specializes in history, space, strange science, and anything out of the ordinary.View full profile James is a ...

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 — ...

Twenty years after Pluto lost its planetary status, the debate continues as scientists still disagree over what defines a planet.