On Feb. 18, 1930, Clyde Tombaugh discovered Pluto, at that time classified as the ninth planet.

Trans-Neptunian objects (TNOs) are icy bodies that vary widely in size, from large dwarf planets like Pluto and Eris—each ...

Explore Ceres, the largest asteroid in our solar system, and discover its remarkable ancient ocean and ice-rich crust.

Planetarium features a number of star shows and laser concerts during March specially designed for children, at 118 Lamington ...

Arizona is most definitely a bucket list state, stacked with unique landscapes found nowhere else, and one-of-a-kind ...

Scientists at NASA for the first time have been able to observe the make up of Pluto and other small and icy celestial bodies ...

Take advantage of a special 6-7 planet alignment from Earth's perspective. Planets 'line up' in the skies over California in ...

Does our Solar System have 9 planets or only 8? Astronomers have gone back and forth on that a lot, with Pluto now being classified as a dwarf planet. However, out beyond Neptune there could be ...

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.

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

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 the bottom of whether Pluto is a planet, I tracked down planetary scientist ...

If planets had social media accounts, the solar system would showcase a frenzy of unique personalities. Mercury tweets at ...