Everyone's favorite dwarf planet, Pluto, was discovered just 95 years ago. Here's the story of how the once-ninth planet was ...

Pluto was discovered at Lowell Observatory in Flagstaff, Arizona in 1930 and was considered our ninth planet until 2006. The International Astronomical Union reclassified Pluto as a dwarf planet ...

Why was Pluto reclassified as a dwarf planet? One might think that it’s purely a matter of size. Mercury, the smallest of the ...

FLAGSTAFF, Az. – Whether Pluto is officially a planet is the least interesting thing about the runt of the solar system, astronomers will tell you 95 years after the discovery of the fascinating ...

Today, when tens of thousands of minor planets have been discovered (most residing in an "asteroid belt" between Mars and Pluto), not even the meanest of teachers would require students to learn ...

This place just made TIME's list of World's Greatest Places of 2025 and Newsweek's 10 best science museums in the U.S. Here's how you can visit.

The complexity of the Plutonian system is reflected in the complexity of Pluto itself. New Horizons discovered that Pluto is home to the largest glacier in the solar system, one measuring more ...

Here are the five most surprising things discovered by the deep-space instrument. After almost a decade in space, the New Horizons probe's close encounter with Pluto lasted just six days as it ...

FLAGSTAFF, Az. – Whether Pluto is officially a planet is the least interesting thing about the runt of the solar system, astronomers will tell you 95 years after the discovery of the fascinating and ...