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 ...

Pluto receives enough sunlight to be about as bright as midday on Earth during specific times, despite being a dwarf planet 7 ...

Is a sun a star or a planet? While science now agrees the sun is a star, new telescopes may soon challenge how we define ...

(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 ...

When you buy through links on our articles, Future and its syndication partners may earn a commission. This image of Pluto was made after the New Horizons spacecraft flew past the dwarf planet on July ...

The debate over Pluto’s planetary status has been ongoing since its reclassification as a “dwarf planet” in 2006 by the International Astronomical Union (IAU). Recent discussions and new scientific ...

The planet Neptune wobbled in its orbit around the Sun. That could only mean one thing, astronomers said: There was a ninth planet out there, somewhere, lurking in the fringes of the solar system.

The director of the American Museum of Natural History's Hayden Planetarium and author of The Pluto Files, Neil deGrasse Tyson, talks about the... Astrophysicist Tyson On 'Pluto Files' The director of ...