Pluto was discovered 95 years ago on Feb. 18, and even though it was demoted nearly two decades ago, it remains a fascinating part of our solar system. "Pluto is a complex and mysterious world with ...

What was discovered in Flagstaff, Arizona, and killed off in Prague? If you answered "Pluto's planethood," your grasp of the astronomical is excellent. Feb. 18 marks the 95th anniversary of the ...

The science community may be ecstatic over the discovery of a ninth planet, but the former planet "Pluto" had a totally different reaction. Hours after scientists announced there's solid evidence of ...

Pluto, discovered in 1930, was once considered the ninth planet in our solar system. In 2006, the International Astronomical Union reclassified Pluto as a dwarf planet because it doesn't meet all the ...

(Correction: An earlier version of this story misstated how far Pluto is from the sun. The correct number is 3.7 billion miles.) What was discovered in Flagstaff, Arizona, and killed off in Prague? If ...