Pluto - Planet X?. The planet Pluto was originally discovered in 1930 in the course of a search for a body sufficiently massive to account for supposed anomalies in the orbits of Uranus and Neptune . Once it was found, its faintness and failure to show a visible disc cast doubt on the idea that it could be Lowell's Planet X. Lowell had made a prediction of Pluto's position in 1915 which had turned out to be fairly close to its actual position at that time; however Ernest W. Brown concluded almost immediately that ...

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Pluto, Pluto - Discovery and naming, Pluto - Orbit, Pluto - Physical characteristics, Pluto - Mass and size, Pluto - Atmosphere, Pluto - Appearance, Pluto - Pluto's moons, Pluto - Charon, Pluto - The outer moons, Pluto - Exploration of Pluto, Pluto - The Pluto debate, Pluto - Planet X?, Pluto - Minor planet?, Pluto - New discoveries, Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia II - Pluto - The Pluto debate

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Pluto, Pluto - Discovery and naming, Pluto - Orbit, Pluto - Physical characteristics, Pluto - Mass and size, Pluto - Atmosphere, Pluto - Appearance, Pluto - Pluto's moons, Pluto - Charon, Pluto - The outer moons, Pluto - Exploration of Pluto, Pluto - The Pluto debate, Pluto - Planet X?, Pluto - Minor planet?, Pluto - New discoveries, Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia II - Pluto - Pluto's moons

Little is known about Pluto because of its great distance from Earth and because no exploratory spacecraft have visited Pluto yet. The Voyager 1 probe was originally intended to visit Pluto, but due to budget cuts and lack of interest — before the discovery of Pluto's moon, size, and atmosphere — the flyby was scrapped in order to facilitate a close flyby of Saturn's moon Titan. The first spacecraft to visit Pluto will be NASA's New Horizons, a mission led by the Southwest Research Institute and ...

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Pluto, Pluto - Discovery and naming, Pluto - Orbit, Pluto - Physical characteristics, Pluto - Mass and size, Pluto - Atmosphere, Pluto - Appearance, Pluto - Pluto's moons, Pluto - Charon, Pluto - The outer moons, Pluto - Exploration of Pluto, Pluto - The Pluto debate, Pluto - Planet X?, Pluto - Minor planet?, Pluto - New discoveries, Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia II - Pluto - Exploration of Pluto

Pluto is the ninth planet in the solar system. Discovered in 1930 and immediately classified as a planet, its status is currently under dispute. Pluto has an eccentric orbit that is highly inclined in respect to the other planets and takes it inside the orbit of Neptune. Its largest moon is Charon, discovered in 1978; two smaller moons were discovered in 2005. Pluto's astronomical symbol is a P-L monogram, ♇. This represents both the first two letters of the name Pluto and the initials of Percival Lowell ...

Including:

Pluto - Discovery and naming Pluto - Orbit Pluto - Physical characteristics
Pluto - Mass and size Pluto - Atmosphere Pluto - Appearance
Pluto - Pluto's moons
Pluto - Charon Pluto - The outer moons
Pluto - Exploration of Pluto Pluto - The Pluto debate
Pluto - Planet X? Pluto - Minor planet? Pluto - New discoveries
Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia - Pluto

The questions are as in many comedy panel games, mainly there to set up jokes or discussions, rather than for any serious competition. Certain questions are purposely contradictory to established doctrine for the sake of entertainment. To take an example; to the question "How many planets are there in the solar system?", Alan Davies gave the answer "nine" and lost points for an obvious and wrong answer, the explanation being that at the time a debate was occurring over whether Pluto was indeed a planet (a debate that has continued to ...

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QI, QI - Format, QI - Episodes, QI - Frequent participants, QI - Criticism, QI - QI culture

Read more here: » QI: Encyclopedia II - QI - Criticism

In the most common usage, a double planet is a set of two planets of comparable mass orbiting one another. Pluto and Charon have consistently been recognized in the literature as representing the only real double planet system in our Solar System today. Double planet - Debate. In this usage, there has been some debate on precisely where to draw the line between a double planet and a planet-moon system. In most cases, it's simply not an issue because the moon is of very small mass relative to its hos ...

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Double planet, Double planet - Two planets orbiting one another, Double planet - Debate, Double planet - Two planets colliding with each other, Double planet - Two planets orbiting a star, Double planet - Asimov's proposed definition

Read more here: » Double planet: Encyclopedia II - Double planet - Two planets orbiting one another

More than 75 years after its discovery, many facts about Pluto remain unknown, mainly due to the fact that it is the only planet that has not been visited by human spacecraft and that it is too far away for in-depth investigations with telescopes from earth. What is known are the few physical properties listed below. Pluto - Mass and size. Pluto is not only smaller and much less massive than every other planet, but at less than 0.2 lunar masses it is also smaller and less massive than seven moons: Ganymede ...

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Pluto, Pluto - Discovery and naming, Pluto - Orbit, Pluto - Physical characteristics, Pluto - Mass and size, Pluto - Atmosphere, Pluto - Appearance, Pluto - Pluto's moons, Pluto - Charon, Pluto - The outer moons, Pluto - Exploration of Pluto, Pluto - The Pluto debate, Pluto - Planet X?, Pluto - Minor planet?, Pluto - New discoveries, Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia II - Pluto - Physical characteristics

Pluto's orbit is unlike those of the other planets. It is highly inclined above the plane of the ecliptic, and highly eccentric (non-circular). The eccentricity of its orbit is such that it crosses the orbit of Neptune, and making Pluto only the eighth-most distant planet from the Sun for part of each orbit; the most recent occurrence of this phenomenon lasted from February 7, 1979 through February 11, 1999. Mathematical calculations indicate that the previous occurrence only lasted fourteen years from July 11, 1735 to September 15, 1749. Ho ...

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Pluto, Pluto - Discovery and naming, Pluto - Orbit, Pluto - Physical characteristics, Pluto - Mass and size, Pluto - Atmosphere, Pluto - Appearance, Pluto - Pluto's moons, Pluto - Charon, Pluto - The outer moons, Pluto - Exploration of Pluto, Pluto - The Pluto debate, Pluto - Planet X?, Pluto - Minor planet?, Pluto - New discoveries, Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia II - Pluto - Orbit

Pluto was discovered by the astronomer Clyde Tombaugh at the Lowell Observatory in Arizona on February 18, 1930 after an extensive search when he compared photographic plates taken on January 23 and 29. After the observatory obtained confirming photographs, the news of the discovery was telegraphed to the Harvard College Observatory on March 13, 1930. The planet was later found on photographs dating back to March 19, 1915. Tombaugh was searching for a "Planet X" to explain discrepancies in the predicted orbit of Neptune. It is now known these discrepancies were an artifact of the slightly incorre ...

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Pluto, Pluto - Discovery and naming, Pluto - Orbit, Pluto - Physical characteristics, Pluto - Mass and size, Pluto - Atmosphere, Pluto - Appearance, Pluto - Pluto's moons, Pluto - Charon, Pluto - The outer moons, Pluto - Exploration of Pluto, Pluto - The Pluto debate, Pluto - Planet X?, Pluto - Minor planet?, Pluto - New discoveries, Pluto - Pluto in popular culture

Read more here: » Pluto: Encyclopedia II - Pluto - Discovery and naming