Pluto is a dwarf planet orbiting the Sun, with about a sixth of the mass of the Moon and a third of its volume. Like other Kuiper belt objects, which are generally outside Neptune's orbit, Pluto is primarily rock and ice. It has an elongated and highly inclined orbit that takes it from 49 astronomical units (7.4 billion km) away from the Sun down to 30, closer than Neptune. Light from the Sun takes about 5.5 hours to reach it at its average distance. Since its discovery in 1930, it had been considered the ninth planet, but the International Astronomical Union came up with a new definition for planets in 2006 that excluded Pluto after many other similar icy objects were found, including Chiron and Eris. Pluto has five known moons: Charon (about half as wide as Pluto), Styx, Nix, Kerberos, and Hydra. On 14 July 2015, a spacecraft is visiting the dwarf planet and its moons for the first time: the New Horizons probe is performing a flyby and attempting to take detailed measurements and images. NASA has invited the general public to suggest names for surface features that will be discovered on Pluto and Charon.

Read more: https://en.wikipedia.org/wiki/Pluto

_______________________________ Today's selected anniversaries:

1223:

Louis VIII became King of France to begin a short three-year reign. https://en.wikipedia.org/wiki/Louis_VIII_of_France

1769:

Spanish soldier Gaspar de Portolà led the first European land expedition to present-day California. https://en.wikipedia.org/wiki/Portol%C3%A0_expedition

1865:

A seven-man team made the first ascent of the Matterhorn, marking the end of the golden age of alpinism. https://en.wikipedia.org/wiki/First_ascent_of_the_Matterhorn

1950:

In an early battle of the Korean War, North Korean troops began attacking the headquarters of the American 24th Infantry Division in Taejon, South Korea. https://en.wikipedia.org/wiki/Battle_of_Taejon

1987:

Over 100 mm (3.9 in) of rain fell in a two-and-a-half-hour period in Montreal, causing severe flooding and over CA$220 million in damages. https://en.wikipedia.org/wiki/Montreal_Flood_of_1987

_____________________________ Wiktionary's word of the day:

hapless: Very unlucky; ill-fated. https://en.wiktionary.org/wiki/hapless

___________________________ Wikiquote quote of the day:

Ever'body might be just one big soul, Well it looks that a-way to me. Everywhere that you look, in the day or night, That's where I'm a-gonna be, Ma, That's where I'm a-gonna be. Wherever little children are hungry and cry, Wherever people ain't free. Wherever men are fightin' for their rights, That's where I'm a-gonna be, Ma. That's where I'm a-gonna be.   --Woody Guthrie https://en.wikiquote.org/wiki/Woody_Guthrie