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Index Planetesimal

Planetesimals are solid objects thought to exist in protoplanetary disks and in debris disks. [1]

41 relations: Accretion (astrophysics), Adhesion, American Astronomical Society, Asteroid, Brownian motion, Chamberlin–Moulton planetesimal hypothesis, Comet, Cosmic dust, Debris disk, Deimos (moon), Disrupted planet, Drag (physics), Formation and evolution of the Solar System, Giant planet, Gravity, Infinitesimal, International Astronomical Union, Jupiter, Kuiper belt, Late Heavy Bombardment, List of interstellar and circumstellar molecules, Mars, Mesoplanet, Nebular hypothesis, Neptune, Oort cloud, Orbital inclination, Phobos (moon), Planet, Planetary nebula, Protoplanet, Protoplanetary disk, Ring system, Small Solar System body, Solar System, Streaming instability, Time capsule, Trojan (astronomy), Viktor Safronov, 4 Vesta, 90 Antiope.

Accretion (astrophysics)

In astrophysics, accretion is the accumulation of particles into a massive object by gravitationally attracting more matter, typically gaseous matter, in an accretion disk.

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Adhesion is the tendency of dissimilar particles or surfaces to cling to one another (cohesion refers to the tendency of similar or identical particles/surfaces to cling to one another).

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American Astronomical Society

The American Astronomical Society (AAS, sometimes spoken as "double-A-S") is an American society of professional astronomers and other interested individuals, headquartered in Washington, DC.

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Asteroids are minor planets, especially those of the inner Solar System.

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Brownian motion

Brownian motion or pedesis (from πήδησις "leaping") is the random motion of particles suspended in a fluid (a liquid or a gas) resulting from their collision with the fast-moving molecules in the fluid.

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Chamberlin–Moulton planetesimal hypothesis

The Chamberlin–Moulton planetesimal hypothesis was proposed in 1905 by geologist Thomas Chrowder Chamberlin and astronomer Forest Ray Moulton to describe the formation of the solar system.

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A comet is an icy small Solar System body that, when passing close to the Sun, warms and begins to release gases, a process called outgassing.

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Cosmic dust

Cosmic dust, also called extraterrestrial dust or space dust, is dust which exists in outer space, as well as all over planet Earth.

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Debris disk

A debris disk is a circumstellar disk of dust and debris in orbit around a star.

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Deimos (moon)

Deimos (systematic designation: Mars II) is the smaller and outer of the two natural satellites of the planet Mars, the other being Phobos.

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Disrupted planet

A disrupted planet is an official astronomical term for a planet, or exoplanet, that has been disrupted, or destroyed, by a nearby, or passing, astronomical body or object, such as a star.

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Drag (physics)

In fluid dynamics, drag (sometimes called air resistance, a type of friction, or fluid resistance, another type of friction or fluid friction) is a force acting opposite to the relative motion of any object moving with respect to a surrounding fluid.

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Formation and evolution of the Solar System

The formation and evolution of the Solar System began 4.6 billion years ago with the gravitational collapse of a small part of a giant molecular cloud.

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Giant planet

A giant planet is any massive planet.

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Gravity, or gravitation, is a natural phenomenon by which all things with mass or energy—including planets, stars, galaxies, and even light—are brought toward (or gravitate toward) one another.

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In mathematics, infinitesimals are things so small that there is no way to measure them.

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International Astronomical Union

The International Astronomical Union (IAU; Union astronomique internationale, UAI) is an international association of professional astronomers, at the PhD level and beyond, active in professional research and education in astronomy.

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Jupiter is the fifth planet from the Sun and the largest in the Solar System.

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Kuiper belt

The Kuiper belt, occasionally called the Edgeworth–Kuiper belt, is a circumstellar disc in the outer Solar System, extending from the orbit of Neptune (at 30 AU) to approximately 50 AU from the Sun.

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Late Heavy Bombardment

The Late Heavy Bombardment (abbreviated LHB and also known as the lunar cataclysm) is an event thought to have occurred approximately 4.1 to 3.8 billion years (Ga) ago, at a time corresponding to the Neohadean and Eoarchean eras on Earth.

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List of interstellar and circumstellar molecules

This is a list of molecules that have been detected in the interstellar medium and circumstellar envelopes, grouped by the number of component atoms.

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Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System after Mercury.

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Mesoplanets are planetary bodies with sizes smaller than Mercury but larger than Ceres.

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Nebular hypothesis

The nebular hypothesis is the most widely accepted model in the field of cosmogony to explain the formation and evolution of the Solar System (as well as other planetary systems).

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Neptune is the eighth and farthest known planet from the Sun in the Solar System.

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Oort cloud

The Oort cloud, named after the Dutch astronomer Jan Oort, sometimes called the Öpik–Oort cloud, is a theoretical cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from.

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Orbital inclination

Orbital inclination measures the tilt of an object's orbit around a celestial body.

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Phobos (moon)

Phobos (systematic designation) is the innermost and larger of the two natural satellites of Mars, the other being Deimos.

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A planet is an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.

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Planetary nebula

A planetary nebula, abbreviated as PN or plural PNe, is a type of emission nebula consisting of an expanding, glowing shell of ionized gas ejected from red giant stars late in their lives.

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A protoplanet is a large planetary embryo that originated within a protoplanetary disc and has undergone internal melting to produce a differentiated interior.

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Protoplanetary disk

A protoplanetary disk is a rotating circumstellar disk of dense gas and dust surrounding a young newly formed star, a T Tauri star, or Herbig Ae/Be star.

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Ring system

A ring system is a disc or ring orbiting an astronomical object that is composed of solid material such as dust and moonlets, and is a common component of satellite systems around giant planets.

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Small Solar System body

A small Solar System body (SSSB) is an object in the Solar System that is neither a planet, nor a dwarf planet, nor a natural satellite.

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Solar System

The Solar SystemCapitalization of the name varies.

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Streaming instability

In planetary science a streaming instability is a hypothetical mechanism for the formation of planetesimals in which the drag felt by solid particles orbiting in a gas disk leads to their spontaneous concentration into clumps which can gravitationally collapse.

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Time capsule

A time capsule is a historic cache of goods or information, usually intended as a method of communication with future people and to help future archaeologists, anthropologists, or historians.

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Trojan (astronomy)

In astronomy, a trojan is a minor planet or moon that shares the orbit of a planet or larger moon, wherein the trojan remains in the same, stable position relative to the larger object.

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Viktor Safronov

Viktor Sergeevich Safronov (Ви́ктор Серге́евич Сафро́нов) (born Velikie Luki, Russia, 11 October 1917 – died Moscow 18 September 1999) was a Soviet astronomer who put forward the low-mass-nebula model of planet formation, a consistent picture of how the planets formed from a disk of gas and dust around the Sun.

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4 Vesta

Vesta, minor-planet designation 4 Vesta, is one of the largest objects in the asteroid belt, with a mean diameter of.

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90 Antiope

90 Antiope is a double asteroid in the outer asteroid belt.

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Planetesimal theory, Planetesimals, Planetessimal.


[1] https://en.wikipedia.org/wiki/Planetesimal

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