The Nice Model, when compared to other models, i.e. Grand Tack Model, best describes the migration of worlds in the early solar system and can explain the stable orbits of objects within our solar system.

Planetary formation: Nice Model
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The Nice Model is not the best model for describing the migration of worlds in the early solar system and cannot explain the stable orbits of objects within our solar system.

Planetary formation: Other theories and models
Created at: 
2020-04-21
  Updated at: 
2020-04-21
Curator:
Reilly Brennan   Subscribe ...

Background

Kuiper Belt Objects

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Focusing on a certain type of asteroids in the Kuiper Belt and Oort Cloud can help better explain planetary migration.

eThe cold population (low orbit eccentricity showing low perturbation to the orbits) of the Kuiper Belt formed where they currently are and were stable during the migration of the outer planets.

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Gravitational instability is one way to describe the formation of the Kuiper Belt.

eThe observed natural tendency for binary (occurs when two objects orbit around a point that lies in between them) Kuiper Belt objects (KBO) and their properties can be a natural consequence of KBO formation by gravitational instability.

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The Kuiper Belt formed during the instability of the orbits of Uranus and Neptune.

eThe Kuiper Belt is a relic of the primordial massive planetesimal disk.

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Kuiper Belt Objects originated in the inner solar system.

eThe solar system spread to its current size during the growth and dynamical evolution of the ice giants, and planetary ejections, which are thought to have populated the Kuiper Belt, are very rare.

Oort Cloud

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Grand Tack Model accurately describes the formation of the Oort Cloud.

eSimulations of the Grand Tack model show that it is an accurate model for finding inner solar system material in the Oort Cloud.

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The Nice Model does not accurately describe the formation of the Oort Cloud.

eSimulations of the Nice Model have proven that it is not an accurate migration theory.

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The analysis of the recently discovered rocky comet C/2014 S3 in the Oort Cloud is evidence that ejections of rocky material to either the Kuiper Belt or the Oort Cloud is possible.

eThe material of the rocky comet C/2014 S3 in the Oort cloud has similar characteristics as S-type asteroids (has a high composition of silicone) found in the Asteroid Belt.

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During the Sun’s migration to its current location, it may have collected comets and rocky material from other stars.

eThe Sun captured comets that now make up its Oort Cloud from other stars while it was still in its initial formation period.

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The Galactic Tides felt by our solar system may be one of the reasons the Oort Cloud is a sphere and not a ring like the Kuiper Belt, and compliments the Nice Model.

eGalactic Tides and passing stars morphed the Oort Cloud into an almost spherical shape.

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While the Sun was moving away from the center of our galaxy, it might have lost some comets to the galactic gravitational pull of the Milky Way Galaxy, meaning that the planetary migration had no effect on the formation of the Kuiper Belt or the Oort Cloud.

eThe Sun’s original galactocentric distance, which was much closer to the center of the Milky Way Galaxy, and its associated stronger gravity might have caused Oort cloud bodies to be stripped or cycled back into the planetary region, closer to the Sun.