As astronomers continue discovering unusual worlds beyond our solar system, many say the question that divided scientists in ...

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 ...

On the 20th anniversary of Pluto’s infamous demotion, Mike “Pluto Killer” Brown explains why any reversal of that decision would be driven more by nostalgia than science ...

Two decades after Pluto was reclassified as a dwarf planet, scientists remain divided over the definition that removed it ...

Learn how Pluto nearly kept its planet status in a proposed 12-planet Solar System as its demotion marks its 20th anniversary.

Unpopular opinion time, Pluto being reclassified as a dwarf planet was a great thing for our understanding of the solar ...

The discovery of the Kuiper Belt revealed thousands of icy objects near Pluto, challenging its status as a planet. After the discovery of Eris, astronomers formally redefined “planet” in 2006, leading ...

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.

Those who supported Pluto’s demotion included Neil DeGrasse Tyson ...

Pluto's demoted status as a dwarf planet turns 20 years old today and isn't even a chink in its armour when it comes to its astrological impact.

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 — ...

Pluto is a bit of a loner. The dwarf planet is no longer considered a regular planet; it does not orbit on the same plane as the solar system's eight planets; and its orbit is both highly elliptical ...