Planetesimal

Planetesimal Theory Related Category: Astronomy: General (pln´´ts´ml): see solar system. More on Planetesimal Theory ...

Definition: planetesimals: Primordial bodies of intermediate size that accreted into planets or asteroids. Space Tragedies9 Planets in Nine DaysAstronomy 101 Related Articles ...

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

Planetesimals have a harder time growing above a few hundred kilometers in size, however.

Planetesimals that became modest in size but did not merge to form larger bodies became asteroids and comets.

planetesimal One of the small bodies that formed from the solar nebula and eventually grew into proto-planets. population I ...

Planetesimal A small body of rock and/or ice - under 10 kilometers (6 miles) across - formed during the early stages of the solar system. Planetesimals are the building blocks of planets, but many never combined to form large bodies.

Planetesimals within the region which would become the asteroid belt were too strongly perturbed by Jupiter's gravity to form a planet. Instead they continued to orbit the Sun as before, while occasionally colliding.

Planetesimal impact First published in 1975, this theory proposes that early in the earth's history, well over 4 billion years ago, the earth was struck by a large body called a planetesimal, about the size of Mars.

PLANETESIMAL A planetesimal is a small object that orbits the Sun. Planetesimals are thought to have formed when the Solar System itself formed, and they were perhaps the building blocks from which the planets were built.

planetesimal - (n.) A small (diameter up to several hundred kilometers) solar-system body of the type that first condensed from the solar nebula. Planetesimals are thought to have been the principal bodies that combined to form the planets.

Planetesimal a rocky and/or icy body, a few to several tens of kilometers in size, that was produced in the solar nebula. Precambrian a geological term denoting the time in Earth history prior to 570 million years ago.

Planetesimals: Bodies ranging in size from meters up to hundreds of kilometers in diameter that formed during the process that formed the planets by accretion. Most planetesimals accreted to form the planets.

planetesimal -- one of the numerous small, solid bodies that, when gathered together, form a planet.

Planetesimals Asteroid-sized solid bodies that are hypothesized to form when the protosolar nebula collapsed into a disk and fragmented. Most of the planetesimals subsequently accumulated into planets. Planetocentric Coordinates ...

Planetesimal - A primordial solar system body of intermediate size that accreted with other planetesimals to form planets and satellites Planetology - The comparative study of the properties of planets Plasma - A fully or partially ionized gas ...

planetesimal Term given to objects in the early solar system that had reached the size of small moons at which point their gravitational fields were strong enough to begin to influence their neighbors. plasma ...

Icy planetesimals formed in the outer solar system. Composition Mainly ice and dust Orbits Highly elliptical, taking them very close to the Sun and back out into deep space, often far beyond the orbit of Pluto.

The planetesimals in the Oort Cloud and Kuiper Belt probably consist of chunks of rock mixed with frozen water and gases. Astronomer Fred Whipple once described them as "dirty snowballs.

Planetoid/Planetesimal: Planetoids are objects that are larger than asteroids but cannot be called a planet. The term planetesimal is sometimes used to refer to asteroids, but also objects with a specific diameter of approx. 10 km.

Comets are icy planetesimals usually from 1 to 50 km across and containing bits of fragile dust resembling carbonaceous chondrite material.

The larger icy planetesimals beyond the frost line became massive enough to capture and hold onto helium and then hydrogen gases, which caused them to rapidly grow into jovian protoplanets.

Most of these icy planetesimals were incorporated into the cores of the giant planets, ...

Within these disks, planetesimals collide and agglomerate into larger protoplanetary bodies that eventually form planets.

Some of the initial planetesimals get ejected out beyond the orbit of Pluto to form the nuclei of the comets. The young sun continues to heat things up, and blows excess gas and dust out of the solar system.

Used for planetesimals. protoplanet (NASA SP-7, 1965) Any of the sun's planets as it emerged or existed in the formative period of the solar system.

The gravity of the planetesimals tended to divide the solar nebula into ring-shaped zones. This process explains item (i) above. F. More massive planetesimals had stronger gravity and could pull in more of the surrounding solar nebula material.

Chamberlin-Moulton planetesimal hypothesis Chameleon (constellation) Chandler wobble Chandra X-ray Observatory Chandrasekhar Limit chaotic inflationary theory chaotic orbit chaotic terrain Chara (Beta Canum Venaticorum) characteristic length ...

It is thought that at the time the planets were forming from the low-velocity collisions among asteroid-size planetesimals, one of them grew at a high rate and to a size larger than the others.

In regions where the average velocity of the collisions was too high, the shattering of planetesimals tends to dominate over accretion, preventing the formation of planet-sized bodies.

The Giant Impactor Theory (sometimes called The Ejected Ring Theory): This theory proposes that a planetesimal (or small planet) the size of Mars struck the Earth just after the formation of the solar system, ...

This suggested the theory that the Moon was produced when a huge planetesimal, perhaps as big as Mars, slammed into the still-forming Earth, ripping material out of its crust.

According to his model, the planets originated from a disk or a ring of dust around the Sun, and cometary nuclei are nothing more than primordial planetesimals that accreted first and became the building blocks of the planets.

What is the difference between a planetesimal and a dwarf planet? Does a black hole gobble up neutrinos, or do the neutrinos just breeze through the black hole as they do through everything else?

These small planetesimals made of rock and ice orbit our Sun past the planet Neptune. They are Kuiper Belt objects left over from the formation of the solar system. Pluto may be a TNO, albeit a rather massive one.

What are comets? A comet is a small world which scientists sometimes call a planetesimal. They are made out of dust, and ice. Kind of like a dirty snow ball. Where do they come from? Comets come from two places: The Kuiper Belt, and the Oort Cloud.

Thomas Chrowder Chamberlain (Sept. 25, 1843 - Nov. 15, 1928) was an American geologist and teacher who proposed the planetesimal hypothesis of the formation of the Solar System.

At this point, the solar system is composed only of solid, protoplanetary bodies and gas giants. The "planetesimals" would slowly collide with each other and become more massive.

The planets were originally formed from planetesimals, sub-planetary bodies that accreted together during the first years of the solar system and no longer exist.

An process involving the selective removal of atmospheric species from impacts of planetesimals.

See also: Planet, Solar, Solar System, Orbit, Sun