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Neptune -

It has been almost 200 years since astronomers discovered a new planet in our solar system. Neptune was found in just one night of planetary observation, when Johann Gottfried Galle and his student pointed a telescope in its direction back in 1846.

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California Institute of Technology -

In 2016, astronomers from the California Institute of Technology (Caltech), Konstantin Batygin and Mike Brown, stated that their research provides evidence for the great possibility of a large planet in the outer solar system.

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Strong evidence -

While the astronomers have not observed the planet, they provide strong theoretical evidence for its existence and information relevant to its potential impact.

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Kuiper Belt -

This evidence looks at the potential relationship and influence of the hypothetical planet on dwarf planets and smaller objects in the Kuiper Belt.

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Planet Nine -

The mystery planet, dubbed "Planet X" (x as in the letter, not the Roman numeral) or "Planet Nine," is thought to be 1.5 times the size of the Earth, sitting far beyond Pluto.

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Mass 5-10 times larger than Earth -

The planet’s mass could be 5-10 times larger than Earth and it could orbit the Sun 20-30 times farther than Neptune. NASA notes that if this theory is accurate, it would take Planet Nine between 10,000-20,000 Earth years just to make one orbit around the Sun.

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Unique orbits -

Astronomers say that the potential existence of this planet could explain certain gravitational patterns in the outer solar system, specifically the unique orbits of dwarf planets and icy objects in the Kuiper Belt.

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Gerard Kuiper -

The Trans-Neptunian Region, more often called the Kuiper Belt, was named after astronomer Gerard Kuiper. It is sometimes referred to as the "third zone" of the solar system; a cold region located in the solar system beyond Neptune’s orbit.

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Icy objects -

In addition to Pluto, astronomers believe that millions of icy objects lie in the Kuiper Belt, including compounds like ammonia and methane.

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Puffy donut -

Known as one of the biggest structures in our solar system, the Kuiper Belt has generally been described as looking like a puffy donut.

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Edge of Neptune’s orbit -

Beginning at the edge of Neptune’s orbit, the Kuiper Belt extends nearly 1,000 AU (1 AU is equivalent to the distance from the Sun to Earth).

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Over 2,000 objects discovered -

While astronomers have only identified around 2,000 objects in the Trans-Neptunian Region, it is likely that there are hundreds of thousands more undiscovered objects; often thought of as "leftovers" from the solar system’s formation.

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Formation of solar system -

The theory about how this happened is that when the solar system was forming, because of shifts in Jupiter and Saturn’s orbits, Uranus and Neptune were required to orbit farther from the Sun.

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Uranus and Neptune -

Drifting further and further away, Uranus and Neptune passed through the icy leftovers after all the huge planets formed.

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Jupiter -

The gravity of Neptune’s orbit tossed these objects toward the Sun and big planets like Jupiter, while Jupiter then flung them either out of the solar system or to distant orbits.

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Fragmented bits -

Neptune’s gravitational power pushed the remainder of the objects into the Kuiper Belt, where they sometimes collide and break into fragmented pieces. 

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Dwarf planets and objects clumped -

Astronomers who have been studying the Kuiper Belt notice that several of the smaller planets and some objects tend to pursue orbits that clump together.

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Theory on Planet Nine -

It’s through the analysis of these orbits, namely gravitational interactions with a huge planet, that astronomers base their theory on the existence of Planet Nine. 

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Some researchers deny its existence -

Some naysayers in the scientific community downplay Planet Nine's potential existence. They argue that the observed orbits are merely due to the random distribution of objects along the belt. 

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All tools being used -

Scientists are desperately trying to find the planet to confirm its existence. Using a dedicated observatory, powerful telescopes, and citizen projects, astronomers are attempting to gather as much data as possible to locate the planet.

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Complex computational simulations -

The current theory is based on complex computational simulations that take into account a number of conditions. The model that most closely aligns with observed orbital patterns is that which includes Planet Nine.

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Vera C. Rubin Observatory -

Scientists are hoping that the new Vera C. Rubin Observatory, located in Chile, will help unlock some of the inquiries relevant to Planet Nine and other astronomical questions.

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Detailed, time-lapse record -

Using innovative technology, the observatory will be able to provide an extensive, detailed record of the Universe over the span of a decade using the largest camera ever built.

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Collected imagery -

The imagery collected by the observatory will be able to provide a more detailed understanding of the distribution of objects along the Kuiper Belt. 

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Why is it so complex to find the planet? -

Locating planets is quite challenging. Astronomers use the transit method to find planets in other solar systems.

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Transit method -

Astronomers may be more likely to locate planets by observing a star’s movement. The computational model used to detect Planet Nine’s existence estimates a 99% probability of its existence.

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Malena Rice -

Assistant Professor of Astronomy Malena Rice from Yale University stated that finding another planet “could completely reshape our understanding of the solar system and of other planetary systems, and how we fit into that context.”

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Mysteries of the outer solar system -

Small black holes, potential alien worlds, additional dwarf planets, volcanic comets, and asteroids, among other possibilities, are just some of the mysteries that astronomers also seek to understand about the outer solar system.

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The quest continues -

While the quest to find Planet Nine continues, some scientists are betting everything on indirect evidence of the planet’s existence, while others hold very skeptical positions.

Sources: (NASA) (AP News) (Live Science) (Yahoo News UK) (Interesting Engineering) (ABC Australia)

See also: Is it possible to bring humans back from extinction?

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