And sure enough, afterward, there was definitely a shift — in Pluto's favor. The images New Horizons sent back were breathtaking, revealing an active, complex planet with mountains, valleys and ...

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 ...

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 ...

(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?

Pluto, with its heart-shaped glacier, as captured by the New Horizons spacecraftJPL/NASA Pluto will mark a birthday of sorts on March 23, 2178. No one is likely to be there to celebrate it, of ...

The search for Pluto did not begin with Clyde Tombaugh ... With family wealth to back him, he founded an observatory in the western dark-sky desert of the U.S. and hoped to unlock the mystery ...