Pluto

American  

[ploo-toh] / ˈplu toʊ /

noun

1. Classical Mythology. a name given to Hades, under which he is identified by the Romans with Orcus.

2. Astronomy. a dwarf planet having an equatorial diameter of about 2,100 miles (3,300 km), a mean distance from the sun of 3.674 billion miles (5.914 billion km), a period of revolution of 248.53 years, and one known moon, Charon. Based on the definition of a planet devised by the International Astronomical Union in 2006, Pluto, regarded as the ninth and most distant planet in our solar system since its discovery in 1930, was reclassified as a dwarf planet, a decision that continues to be examined and questioned by some astronomers.

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Pluto ¹ British  

/ ˈpluːtəʊ /

noun

1. the second-largest dwarf planet in the solar system, located in the Kuiper belt; discovered in 1930 by Clyde Tombaugh (1906–97); classified as a planet until 2006, when it was reclassified as a dwarf planet. It has a diameter of 2390 km

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PLUTO ² British  

/ ˈpluːtəʊ /

noun

1. the code name of pipelines laid under the English Channel to supply fuel to the Allied forces landing in Normandy in 1944

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Pluto ³ British  

/ ˈpluːtəʊ /

noun

1. classical myth the god of the underworld; Hades

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Pluto Scientific  

/ plo̅o̅′tō /

1. A dwarf planet that until 2006 was classified as the ninth planet in the Solar System. Pluto was not discovered until 1930, when Clyde Tombaugh noticed it while searching for an unknown planet thought to influence Uranus's orbit. Pluto's surface is covered with frozen methane and other ices, and its extremely thin atmosphere consists primarily of methane and nitrogen. Between 1979 and 1999 Pluto crossed inside Neptune's orbit. Pluto has three moons: Charon (discovered in 1978) and Hydra and Nix (both discovered in 2005).

2. See Table at solar system

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Pluto ¹ Cultural  

1. The Roman name of Hades, the Greek and Roman god of the underworld and ruler of the dead.

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Pluto ² Cultural  

1. In astronomy, the smallest of the major planets, usually ninth from the sun. Pluto was discovered in 1930 and is named for the Roman god of the underworld. (See solar system)

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Discover More

The planet Pluto is usually the most distant planet in the solar system.

Astronomers in the late nineteenth century, thinking they saw disturbances in the orbits of Uranus and Neptune, suspected that there was a ninth planet, not yet discovered, exerting gravitation on the other two. In the early twentieth century, astronomers searched for that planet and found Pluto. Ironically, Pluto is much too small to be the planet they sought.

There is some debate among astronomers as to whether Pluto should really be classified as a planet or should instead be considered a large asteroid-like body.

Pluto's orbit is a stretched ellipse, unlike the orbits of the other major planets, which are nearly circular. As a result, for a period ending in 1999, Pluto was actually closer to the sun than Neptune.

Etymology

Origin of Pluto¹

Latin, from Greek Ploutōn, literally: the rich one

Origin of PLUTO¹

C20: from p ( ipe ) l ( ine ) u ( nder ) t ( he ) o ( cean )

Example Sentences

The adult western drama with James Arness is finding loyal fans and new audiences on Peacock, Paramount+ and Pluto TV.

From Los Angeles Times

This broader interpretation also aligns with the finding that Pluto, a dwarf planet, is dominated by rock.

From Science Daily

Quarterly Revenue for the streaming operations, including Pluto TV, was up 17%.

From Los Angeles Times

Since then, Pluto, our beloved ninth planet, has been demoted to a dwarf planet.

From Space Scoop

Cindy Holland, a former top Netflix programmer, will run the streaming services, Paramount+ and Pluto, making her a major player in the new company.

From Los Angeles Times

Related Words

• earth