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A whirling cloud of gas or dust that becomes a planet by condensation during formation of a solar system. As the central body, or protostar, of the system contracts and heats up
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How many times has the Earth collapsed?
The Earth never collapsed. In the beginning of formation (about 4.6 billion years ago), however, it is theorized that a protoplanet, the size of Mars, sideswiped the Earth and caused a portion of both to break apart. The pieces came together and formed the Moon. It is also theorized that the Earth became a snow ball twice. There were also asteroid impacts on Earth, some severe enough to end most of life, but the Earth itself stayed intact.
How are moon rocks used to determine the age of the Earth?
The oldest moon rocks are actually older than the oldest Earth rocks. The moon formed from accreted material that resulted from a collision between Earth and a Mars sized protoplanet. Both the Earth and the moon were molten for a period after the collision. Because of the moon's smaller size, it's surface cooled very quickly compared to the Earth. The solidified magma (rock) that formed the moon's crust has been dated at roughly 4.4 billion years of age. Even though no Earth rock has been found to date this old, we can still reasonably assume that the Earth is at least that old due to the fact that the moon is formed from accreted material from the previously mentioned collision.
How scientists believe the earth's four layers formed?
Currently most geologists favor the theory that earth formed via accretion from a protoplanetary cloud about 4.57 billion years ago. The material that formed the terrestrial planets like Earth contained a concentration of short-lived radionuclides that was high enough that the radiation emitted by their decay heated the bodies up to their melting temperature. An additional source of energy for Earth is believed to be the so-called "giant impact", the collision of the proto-Earth with a roughly Mars-sized protoplanet in the early history of our planet. It is thought to have resulted in the complete melting of the upper 100s of km of the Earth. In the its molten stage the Earth completed its differentiation (separation of elements that chemically are unsoluable within each other in large quantities) into a metal core and a silicate mantle. As the Earth is loosing heat into space the inner part of the metal core started to crystallize and now forms the (I) solid inner core. (II) The outer metal core is still liquid and is believed to play a key role in generating the Earth's magnetic field. (III) The mantle is the shell around the core which is currently not very well understood in terms of its exact composition and rheological (the way that the material reacts on stresses leading to deformation) behaviour. Most geologists agree that the whole mantle or at least a portion of it convects and by this process the mantle in mixed and portions of the mantle ascend to rather shallow (i.e. close to the surface) levels and undergo partial melting. Formally the mantle can be subdivided into several zones depending on the stability of certain mineral phases and one often finds the subdivision into upper and lower mantle at a depth of about 660 km. (IV) The melt extracted from the mantle forms most of the oceanic crust that we see today and is the first step to the creation of continental crust as well. The formation of continental crust is far more controversial than that of oceanic crust but involves melt extraction from the mantle and several remelting events of the basalts that crystallized from these melts. The continental crust as we know it today is buoyant, i.e. it "floats" on the mantle because of its lower density and builds stable land masses whereas the oceanic crust is continuously recycled and sinks into the mantle in subduction zones.
What best describes the crust in science?
In geology, the crust is the outermost solid shell of a rocky planet or natural satellite, which is chemically distinct from the underlying mantle. The crusts of Earth, the Moon, Mercury, Venus, Mars, Io, and other planetary bodies have been generated largely by igneousprocesses, and these crusts are richer in incompatible elements than their respective mantles.Earth's crustThe internal structure of EarthThe crust of the Earth is composed of a great variety of igneous, metamorphic, and sedimentary rocks. The crust is underlain by the mantle. The upper part of the mantle is composed mostly of peridotite, a rock denser than rocks common in the overlying crust. The boundary between the crust and mantle is conventionally placed at the Mohorovičić discontinuity, a boundary defined by a contrast in seismic velocity. The crust occupies less than 1% of Earth's volume.[1]The oceanic crust of the sheet is different from its continental crust.The oceanic crust is 5 km (3 mi) to 10 km (6 mi) thick[2] and is composed primarily of basalt, diabase, and gabbro.The continental crust is typically from 30 km (20 mi) to 50 km (30 mi) thick and is mostly composed of slightly less dense rocks than those of the oceanic crust. Some of these less dense rocks, such as granite, are common in the continental crust but rare to absent in the oceanic crust.Both the continental and oceanic crust "float" on the mantle. Because the continental crust is thicker, it extends both to greater elevations and greater depth than the oceanic crust. The slightly lower density of felsic continental rock compared to basaltic oceanic rock contributes to the higher relative elevation of the top of the continental crust. As the top of the continental crust reaches elevations higher than that of the oceanic, water runs off the continents and collects above the oceanic crust. Because of the change in velocity of seismic waves it is believed that beneath continents at a certain depth continental crust (sial) becomes close in its physical properties to oceanic crust (sima), and the transition zone is referred to as the Conrad discontinuity.The temperature of the crust increases with depth, reaching values typically in the range from about 200 °C (392 °F) to 400 °C (752 °F) at the boundary with the underlying mantle. The crust and underlying relatively rigid uppermost mantle make up the lithosphere. Because of convection in the underlying plastic (although non-molten) upper mantle and asthenosphere, the lithosphere is broken into tectonic platesthat move. The temperature increases by as much as 30 °C (about 50 °F) for every kilometer locally in the upper part of the crust, but the geothermal gradient is smaller in deeper crust.[3]Plates in the crust of EarthPartly by analogy to what is known about the Moon, Earth is considered to have differentiated from an aggregate of planetesimals into its core, mantle and crust within about 100 million years of the formation of the planet, 4.6 billion years ago. The primordial crust was very thin and was probably recycled by much more vigorous plate tectonics and destroyed by significant asteroid impacts, which were much more common in the early stages of the solar system.Earth has probably always had some form of basaltic crust, but the age of the oldest oceanic crust today is only about 200 million years. In contrast, the bulk of the continental crust is much older. The oldest continental crustal rocks on Earth have ages in the range from about 3.7 to 4.28 billion years [4][5] and have been found in the Narryer Gneiss Terrane in Western Australia, in the Acasta Gneiss in the Northwest Territories on the Canadian Shield, and on other cratonic regions such as those on the Fennoscandian Shield. Some zircon with age as great as 4.3 billion years has been found in the Narryer Gneiss Terrane.The average age of the current Earth's continental crust has been estimated to be about 2.0 billion years.[6] Most crustal rocks formed before 2.5 billion years ago are located in cratons. Such old continental crust and the underlying mantle asthenosphere are less dense than elsewhere in Earth and so are not readily destroyed by subduction. Formation of new continental crust is linked to periods of intense orogeny; these periods coincide with the formation of the supercontinents such as Rodinia, Pangaeaand Gondwana. The crust forms in part by aggregation of island arcs including granite and metamorphic fold belts, and it is preserved in part by depletion of the underlying mantle to form buoyant lithospheric mantle.CompositionMain articles: Abundance of elements in Earth's crust and Goldschmidt classificationAbundance (atom fraction) of the chemical elements in Earth's upper continental crust as a function of atomic number. The rarest elements in the crust (shown in yellow) are not the heaviest, but are rather the siderophile (iron-loving) elements in the Goldschmidt classification of elements. These have been depleted by being relocated deeper into Earth's core. Their abundance in meteoroidmaterials is higher. Additionally, tellurium and selenium have been depleted from the crust due to formation of volatile hydrides.The continental crust has an average composition similar to that of andesite.[7] Continental crust is enriched in incompatible elements compared to the basaltic ocean crust and much enriched compared to the underlying mantle. Although the continental crust comprises only about 0.6 weight percent of the silicate on Earth, it contains 20% to 70% of the incompatible elements.Most Abundant Elements of Earth's Crust Approximate % by weight O 46.6 Si 27.7 Al 8.1 Fe 5.0 Ca 3.6 Na 2.8 K 2.6 Mg 1.5 Oxide Percent SiO2 60.6 Al2O3 15.9 CaO 6.4 MgO 4.7 Na2O 3.1 Fe as FeO 6.7 K2O 1.8 TiO20.7 P2O5 0.1 All the other constituents except water occur only in very small quantities and total less than 1%. Estimates of average density for the upper crust range between 2.69 and 2.74 g/cm3 and for lower crust between 3.0 and 3.25 g/cm3.[8]Moon's crustMain article: Geology of the MoonA theoretical protoplanet named "Theia" is thought to have collided with the forming Earth, and part of the material ejected into space by the collision accreted to form the Moon. As the Moon formed, the outer part of it is thought to have been molten, a "lunar magma ocean." Plagioclase feldsparcrystallized in large amounts from this magmaocean and floated toward the surface. The cumulate rocks form much of the crust. The upper part of the crust probably averages about 88% plagioclase (near the lower limit of 90% defined for anorthosite): the lower part of the crust may contain a higher percentage of ferromagnesian minerals such as the pyroxenes and olivine, but even that lower part probably averages about 78% plagioclase.[9] The underlying mantle is denser and olivine-rich.The thickness of the crust ranges between about 20 and 120 km. Crust on the far side of the Moon averages about 12 km thicker than that on the near side. Estimates of average thickness fall in the range from about 50 to 60 km. Most of this plagioclase-rich crust formed shortly after formation of the moon, between about 4.5 and 4.3 billion years ago. Perhaps 10% or less of the crust consists of igneous rock added after the formation of the initial plagioclase-rich material. The best-characterized and most voluminous of these later additions are the mare basalts formed between about 3.9 and 3.2 billion years ago. Minor volcanism continued after 3.2 billion years, perhaps as recently as 1 billion years ago. There is no evidence of plate tectonics.Study of the Moon has established that a crust can form on a rocky planetary body significantly smaller than Earth. Although the radius of the Moon is only about a quarter that of Earth, the lunar crust has a significantly greater average thickness. This thick crust formed almost immediately after formation of the Moon. Magmatism continued after the period of intense meteorite impacts ended about 3.9 billion years ago, but igneous rocks younger than 3.9 billion years make up only a minor part of the crust.[10]
What does the protoplanet hypothesis describe the formation of?
the solar system
What happened to the protoplanet because of the heat?
This sucks jon haddad
What is one of the accepted theories of the formation of the moon?
An early collision by (proto) Earth with a large protoplanet..
How did we get the moon where did it come from?
Currently, the most accepted theory is that it resulted from a crash between a large planetoid (or "protoplanet") and Earth.
Can a planet get a large moon from an enormous collision?
Yes, that is how Earth's formed, it hit a large protoplanet called Theia.
Theory about the origin of the moon?
There are several, but one of the more popular is that a protoplanet about the size of Mars originally shared Earth's orbit. It crashed into Earth, and threw off a gigantic cloud of debris that coalesced into the Moon. If you'd like to read more about this, look up "Theia", the name given to this hypothetical protoplanet.
Why photoplanet hyphothesis for the formation of the solar system?
I think you mean "protoplanet hypothesis". In fact, astronomers usually call it the Nebular Hypothesis A protoplanet is a planet-like object that hasn't fully developed into a planet. Why that hypothesis? It's because it is the best we have to describe the origin of the solar system according to the Laws of Physics.
Is an asteroid a terrestrial or a gas giant?
An asteroid is a minor planet that can lean towards terrestrial objects such as the rocky protoplanet-asteroids of Vesta and Pallas.
What were the sources of heat for the protoplanet?
the sources of heat is the sun and the solar system this makes the earth have heat and energy. The sun is the earth main source of heat and energy
How many hours does it take for Ceres?
Ceres is probably a surviving protoplanet, which formed 4.57 billion years ago in the asteroid belt between Mars and Jupiter
When was the moon first created?
No one was around at the time, so we're not really sure, but the current hypothesis in favor is called the "Giant Impact Hypothesis." It posits that a protoplanet about the same size as the current planet Mars struck the proto-Earth while it was still forming, and "splashed" a lot of rock off. This eventually formed the Moon, while the rest of this protoplanet (named Theia) joined with the Earth.
What is the protoplanet?
The hypothesis states that during the formation of a star, the original nebula disk may be so massive that upon further contraction and flattening, it breaks into separate clouds (vortices) or protoplanets.
