“New Horizons shattered a major paradigm of planetary science,” says Alan Stern, the mission’s principal investigator. “Pluto ...

Feb. 18 marks the 95th anniversary of the discovery of our outermost planet-not-planet. Here's what to know about the short ...

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

Pluto may not be a planet any more, but you still have a chance to see the distant dwarf planet at one of Michigan's ...

On the 95th anniversary of its discovery, Pluto remains one of the most beloved and enigmatic worlds in our solar system, ...

An amateur astronomer discovered Pluto 95 years ago today. The former planet will complete an orbit in another 153 years.

Why is Pluto no longer a planet? Discover the real reason behind Pluto’s reclassification as a dwarf planet and the science that led to this change.

According to a recent YouGov poll, 35% of Americans think Pluto is not a planet. But they are all wrong—kind of. To get to ...

Tombaugh's photos that led to the discovery of Planet X. Pluto never really fit in with the other planets in the solar system. Its orbit was out of plane with the other planets. From 1979 to 1999 ...

At the time, Pluto was assumed to be a planet due to its orbit around the Sun, despite being much smaller than initially believed. The name "Pluto" was suggested by Venetia Burney, an 11-year-old ...

Saturn, Venus, Neptune, Uranus, Jupiter, Mars and Mercury will be visible in an uncommon planetary alignment this month.

In August 2006, the International Astronomical Union made the controversial, but correct, decision to demote Pluto from its ...