What causes planets to form in the first place?
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Planet formation is still somewhat of a mystery, but astronomers believe they understand the basic process. The best explanation to be accepted by most astronomers is known as the solar nebula hypothesis. Stars are formed from giant clouds of gas and dust known as nebulae. Gravity causes the matter in the nebula to coalesce. Gravity soon causes the central part of the nebula to collapse and form a star. The rest of the gas and dust forms a flat, rotating ring around the new star. Eventually the gravity of the new star begins to pull matter towards it. Small whirlpools of spinning matter form within this disk. Gravity causes these whirlpools to aggregate into small masses known as planetesimals. These planetesimals continue growing, pulling in the matter around them. Gravity soon pulls them into a spherical shape. These small spheres may collide and merge with others as they grow in size and become what is known as a protoplanet. Sometimes, a smaller sphere of matter may become captured by a larger one and enter into an orbit, creating a moon. Over time, gravity causes the heavier elements in the protoplanets to separate from the lighter ones in a process called uniformitarianism. This forms the planet's metal core, rocky crust, and usually an atmosphere composed of gas. As the star and planets continue to grow, the dust and gas of the nebula begins to thin. Smaller chunks of condensed matter is left over in the outer regions of the disk. These form the Kuiper belt of planetoids and the Oort cloud of comets. Eventually the solar wind from the star will blow away the excess gas and dust. A new solar system has been born. The process is slow and takes millions of years. Many stars have been observed to have flat disks of matter around them. These could very well be new solar systems in the making.
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It was formed from the ring of dust and debris orbiting the sun when the sun gained enough mass to start the fusion process.  It was formed in the same way and at the same time as all the other planets.
803114
Well, it's the general belief that this is how the planets formed in the first place.  When our Sun formed from a big cloud of dust and gas some 4.5 billion years ago, there was left-over material in a disc around it.  Particles of dust in the disc clumped together to make "planetesimals", which in turn clumped together to make planets.  If the new planet was large enough and in the right region of the solar system, it could pull in gas, too.  That's why the larger planetesimals which were further out became the gas giants.\n\nOur solar system is fairly stable now, with each planet in its own "orbital zone" so this doesn't happen too much any more.  Still, this is a really interesting question, so let's imagine that we have some future technology where we could bring some large supply of asteroids to the Earth and add them to its mass.  (Note, however, that even the combined mass of the main asteroid belt between Mars and Jupiter still has much less mass than even our moon, so we'd have to find some magical source of material.)\n\nSince our mass would be increasing, the first thing we'd notice would be increased gravity on the surface.  We'd have to be careful, though, because by adding the extra mass we're decreasing the gravitational potential energy of the asteroids we brought in...all that energy has to go somewhere, most likely into heating up the Earth.  If we added enough asteroids, it might be enough to boil the oceans and melt the Earth's crust, in which case we'd all be in big trouble.\n\nSomething else to consider is any "angular momentum" (such as rotation or the "spinniness" of the orbit) the asteroid might have...If the asteroid was orbiting or rotating in the same direction as Earth, we'd speed up the Earth's rotation and thus shorten the length of our day.  Similarly, if the asteroid had angular momentum in the opposite direction of Earth, the Earth would slow down and the days would be longer.\n\nNow if we keep adding mass, we're going to get a very large planet indeed.  Eventually we'd get to the mass of Jupiter (which is 317 times as massive as the Earth)...but if we're adding asteroids (which are mostly rock with some metal and carbon), we probably wouldn't be a gas giant like Jupiter since there's not a lot of gas in the asteroids.  Some of the rock might vaporize and we might get increasing volcanic activity which would thicken our atmosphere, but we'd have nowhere near the gas content of Jupiter.  Deep in the interior of our Mega-Earth, metals would sink to the core while molten rock would float above...all this increased metal in the core would probably strengthen our magnetic field.  As the heat increased even more, molecules would start to break apart.\n\nAs we start adding more mass, something weird happens.  All that pressure in the core would cause the material to become "degenerate matter", a rare and exotic form of matter in which you can think of the electrons in the atoms as running out of room to get denser, so instead they just start moving faster.  One of the strange properties of degenerate matter is that as you add more matter, it actually shrinks!  So as we add more mass, the planet's size would actually start getting smaller.\n\nOnce we got to 8 times the mass of Jupiter, something special happens.  There would be so much heat and pressure at the planet's core that deuterium (a certain kind of isotope of hydrogen) can start undergoing nuclear fusion...this would produce lots of heat at the center which would casue us to start expanding again.  This is what astronomers call a "brown dwarf", somewhere between a planet and a star.  However, deuterium is not super-common, so brown dwarfs usually just fizzle out once they burn up all their deuterium.\n\nOnce we reached 80 times the mass of Jupiter then suddenly there's enough heat and pressure to star
330346
As of right now, scientists believe that planets are by-products of the formation of stars. A star is formed when particles in a swirling cloud of dust and gas (a nebula) get closer and closer together and begin to combine hydrogen atoms to form helium atoms. This produces lots of energy (which is why stars, like the Sun, shine). Planets are the leftover "clumps" of dust and gas that do not produce their own energy.
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The effect known as the Gyrous of Rotation causes planets to spin. When the planet is born and begins to condense out of its accretion disc it contracts and this puts a turning moment about the planets common centre, similar to a ballet dancer pulling in their arms in order to spin faster. JULES
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Stars and planets form as a result of the gravitational collapse of accreting material. Any net translational motion of that initial material is accelerated as its radius of rotation decreases. This is due to the same conservation of angular momentum principle that makes skaters and divers spin more rapidly when they bring their arms closer to their bodies. In its extreme, this effect can make collapsed neutron starts spin many times each second, creating the regular beat of pulsars as observed from Earth. \n\nOnce an initial spin was established for the Earth, the same conservation principle says that its angular momentum will continue unless it can be transferred to another object. With no significant frictional forces to allow that to happen, the Earth can continue to spin indefinitely without any further prodding.\n\nColliding with Mars? I don't think so!!!!!
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now i dont know much detail, but according to science, there was what is called the Big Bang.  here, this big, huge gas ball started spinning really really fast and formed the milky way, then, smaller gas balls were formed which are the plantes.  then the moons are astroids lurned into the planet's gravitational force.  (just remember-this is not detailed ONE BIT and i might even be wrong on some of this-but the basic idea is correct.)
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Most heavenly bodies were created from dust and small material. There are gravitational forces, however small, between these materials. \n\nAs the materials are attracted to each other by gravity, a "gravitational well", or deformation of space, occurs, much like the water in a draining sink. The material begins to spin "downward" toward the center of the gravitational well.\n\nThe paths of the materials begin to form a rotational pattern. Over eons, the materials join together to form larger masses. These masses eventually form the heavenly bodies. Depending on how much material is present, various types and sizes of heavenly bodies are created (e.g. stars, planets, galaxies). The rotational momentum from the early formation continues as the bodies get larger, thus the spin.\n\nHope this helps!
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When the earth was forming it was extremely hot and water existed merely as vapour, if it fell it never reached the ground being in suspension constantly. Then when the first rains fell boy did they fall, and the rain cycle began.\n\nVapour clouds came first.
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Technically, the general rotation direction of the Sun and most planets is a leftover from the original solar nebula from which the Solar System formed.  As the planets and Sun coalesced, they retained the rotation direction of the original nebula.\n\nDuring the coalescence phase, asteroid-size chunks collided and stuck together.  As more and more of these chunks collected, the planets grew in size.  However, these chunks not only brought mass to the mix, they also brought momentum.  Since most of the materials were probably all travelling in more or less the same direction, the general rotation direction of the growing planets remained the same.\n\nIn the case of Venus and Uranus, it is suspected that a major collision between the planet and another body literally tipped the planets over due to an off-center orientation of the collision.  Uranus tipped over on its side, probably due to its size relative to the other body.  Venus, being smaller, tipped so far over that its rotation was reversed.
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The solar system was formed from the debris of earlier stars.  As the dust and particles collided and formed bigger chunks, they began to exert a gravitational attraction to each other.  These particles began to rotate around a central point (what would eventually become the sun).\n\nThe sun was formed from the majority of the matter.  Once the sun reached critical mass, it started the fusion reaction that powers the sun still to this day (Fusion of hydrogen into helium).\n\nThe gravitational pull of the sun caused the terrestrial (or rocky) planets to form from the heavier debris that was drawn in closer (and in a faster orbit).  These planets are Mercury, Venus, Earth and Mars.\n\nThe lighter gasses didn't have as much gravitational attraction as the heavier minerals and these gasses formed the gas giants of our solar system (much further out away from the sun and in a slower orbit).  These planets are Jupiter, Saturn, Uranus and Neptune.\n\nThe last planet, Pluto, is an exception.  It was formed of the left-over debris at the outer edge of the solar system.  It reallys isn't a true planet, more of a Keiper belt object; like a large asteroid.
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They start out as an enormous gas cloud. Gravity causes the parcicles in the cloud to spin around the point of center mass, and the velocity of the spin subsequently flattens it into a disk. That's how galaxies, and on a much smaller scale, planetary systems form.
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I go with the Big Bang theory and that our planet just happened to be in the right place at the right time. If our planet grew life then there is the possibility that other planets in other galaxies grew life as well. We just happened to get the right amount of heat and light from the sun.
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You must be very young because they teach this in grammar school. It started with the big bang, debris was scattered far out into space, them gravity took over forming the planets we know of today.
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That's a good question. I'm quite sure "God made it" isn't the answer you're looking for, especially since you posted this in the science section. \n\nReligion seems to have all the answers, but those answers never satisfy the appetite of curiosity and learning. Below are several different worded versions of the same basic theory of how the Earth (and other planets) formed. \n\nBe sure to check out the sources.\n\n1. The planets formed from the material left over as a result of our sun's formation. As the nebulous cloud condensed and began to rotate, most of the gas condensed into what is now our sun. The remaining material formed what is now the planets and the other bodies in our solar system.\n\n2. The prevailing theory is that they are formed from those remnants of a nebula that do not condense under gravity to form a protostar. Instead, these remnants become a thin disc of dust and gas revolving around the protostar and begin to condense about local concentrations of mass within the disc. These concentrations become ever more dense until they collapse inward under gravity to form protoplanets. When the protostar has grown such that it ignites to form a star, its solar wind blows away most of the disc's remaining material. Thereafter there still may be many protoplanets orbiting the star or each other, but over time many will collide, either to form a single larger planet or release material for other larger protoplanets or planets to absorb. Meanwhile, protoplanets that have avoided collisions may become moons of larger planets.\n\n3. The most widely accepted model for the origin of the Solar System is called the  nebula theory. Most generally phrased, the theory states that the Solar System condensed from a large, lumpy cloud of cold gas and dust.\n\n4. Solar Nebula Theory
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Actually, all of them simultaneously. Sun and the planets were all formed from the remnant gas cloud of the supernova explosion of a star much larger than Sun. While most of the gas cloud fell back to the center forming our Sun, the most dominant center of the materials in the peripheral volume ended up forming Jupiter, the largest planet.\n\nTherefore when the solar system is in its nascent stage of formation, if you see which proto-planet has formed ahead of other planets, you may see Jupiter to be the first, but other planets have also started developing, depending on what's your yardstick of measurement for calling an object a planet.\n\nClearly 4-5 billion years ago, when the protoplanets were still under development, there were still numerous smaller size objects whirling around Sun and the gas cloud would still not have settled.
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The matter that made up the sun and planets existed at one time as a very large disk. As the matter clumped together, it was already on the same plane. That's the theory, anyway.