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 course.

No longer a planet but not forgotten, Pluto’s colors, captured by NASA almost 10 years ago, continue to dazzle among the collection of colorful celestial objects only seen in the solar system. Since ...

Once the quirky underdog of our solar system, Pluto held planetary status until 2006, when it got a cosmic demotion that still stings space fans. Discovered in 1930, Pluto was the ninth planet for ...

Things have been a mess since Pluto's demotion. When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. In 2006, the International Astronomical Union ...