Although telescopes from Earth detected gases on Pluto in 1988, researchers surmised that the tiny planet was losing them too quickly to build up a permanent layer in its skies. But when New ...

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

This new theory helps explain the large, 1,600-kilometer-wide heart-shaped area on Pluto's surface covered by a thick layer of nitrogen ice, which has intrigued scientists since its discovery by ...

(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?

The controversy endures over Pluto's true status, but the solar system underdog continues to capture hearts across the globe. Clyde Tombaugh didn't set out to discover Pluto when he sent his ...

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 ...