An amateur astronomer discovered Pluto 95 years ago today. The former planet will complete an orbit in another 153 years.

On the 95th anniversary of its discovery, Pluto remains one of the most beloved and enigmatic worlds in our solar system, ...

Clyde Tombaugh discovered Pluto in 1930 at Lowell Observatory in Flagstaff. Here's how Pluto won - and lost - its planetary status.

Saturn, Venus, Neptune, Uranus, Jupiter, Mars and Mercury will be visible in an uncommon planetary alignment this month.

Pluto may not be a planet any more, but you still have a chance to see the distant dwarf planet at one of Michigan's ...

“New Horizons shattered a major paradigm of planetary science,” says Alan Stern, the mission’s principal investigator. “Pluto ...

Explore Ceres, the largest asteroid in our solar system, and discover its remarkable ancient ocean and ice-rich crust.

Last fall, the scientific community went into a minor frenzy. A hunk of interstellar material had been sucked into the ...

To explain the planet’s dynamism, “we had to come up with creative ideas.” Puny Pluto demonstrates that tiny planetary specks ...

Take advantage of a special 6-7 planet alignment from Earth's perspective. Planets 'line up' in the skies over California in ...

For decades, Pluto was celebrated as the ninth planet of our solar system. However, in 2006, the International Astronomical ...

In August 2006, the International Astronomical Union made the controversial, but correct, decision to demote Pluto from its ...