Why aren't the particles in the rings of Saturn pulled down to the planet by gravity?
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The particles that make up the rings of Saturn don’t get pulled down to the planet because they orbit the planet.  They remain in orbit for the same reason the Moon or the Space Shuttle remain in orbit around Earth.  In fact, you can think of them as billions of tiny “moonlets”:  they don’t sit still but instead revolve around the planet in predictable (although often complicated) orbits.\n\nAny orbit is a balance between gravity and the motion of the orbiting body.  Objects close to the parent body must orbit more quickly to counteract the stronger pull of gravity—for example, Mercury moves faster in its orbit around the Sun than Earth does—but any orbit constitutes an equilibrium between gravity and momentum.\n\nThat said, Saturn’s rings represent a complicated example of this kind of equilibrium.  Not only does one have to consider the gravitational attraction of Saturn itself, but also of its major moons (Titan, for exampl) and all the aforementioned “moonlets” spinning around the planet.  The results are often surprising:  we see “shepherd” moons that keep rings herded in place, strange propeller-like structures, and even braided rings!  (Links below to some images of these oddities.)\n\nBut the short answer to your question is that the rings, made up of billions of particles, remain constantly in motion, counteracting the pull of gravity.\n\n\nRyan Wyatt\nRose Center for Earth & Space
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That's a mystery that the physicists haven't figured out.  \n\nAristotle theorized that the objects "want" to go toward the middle of the earth.  We might laugh, but think he has a point.  A common theme throughout reality is that things want to go toward equilibrium, and if you keep wanting to go toward something, or have a pull toward something, then you aren't at equilibrium.\n\nPhysicists theorize about gravitons, particles that are gravity.  I think that's wrong.  I believe that gravity is working on the stuff that space is made of.  I believe that the natural state of the universe is probably a singularity.  And when it's not in this state, it tries to return to this state.
1041594
Things that are orbiting our planet are in a state of constant "free fall". That is why they appear to be weightless. The force of gravity is still very high on the astronaut.
474558
The wall does attract objects gravitationaly, but gravity is an exceptionally weak force, and is only noticeable to us humans when dealing with extremely massive objects (like planets, for example).  Gravity is so weak, in fact, that all you have to do to overcome the gravitational pull of the entire Earth is jump.
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With an orbit of where earth is, 149,600,000 km, that's a surface area of 7.12383E+15 km², i think...\n\nYou can fit approx. 11,700 earths in a single ring around the sun, so you can imagine the amount of materials needed for a dyson sphere is pretty massive! (although Jupiter is more than a 1000 times more massive than the earth!)\n\nI think you might even need to destroy whole solar systems to get the materials required, but the planets, moons & asteriod belt would be a good place to start, assuming you need specific materials like metals especially.\n\nDon't even think about the cost!
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The density of it causes it to have more mass, making it have more gravity, meaning it attracts to itself more than anything else on earth pulling it to the center.\n\nMore mass = more gravity.\n\nGravity pulls two objects together. We don't see this because things we see it's too small to notice, but say the earth is attracted to the sun and that's what keeps us in orbit, a black hole is made up of material that is VERY dense and that's why it pulls everything in so strongly, so strong even light doesn't escape. \n\nSo the densest layer of a planet is in the center, and the least dense is on the outer, unless another scientific principle outwieghs that one in application.\n\nImagine a block of iron and a bag of dirt, which would you feel pulling toward the earth stronger?\nYou would percieve the block of iron going toward the surface of the earth stronger than a bag of dirt, but if you think about it it's also moving toward the center of the earth. So that's what happens, the metal is in the middle and the dirt is on the surface.
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At the temperatures on Saturn, water would be frozen solid below the methane atmosphere, so we can't say anything about water molecules on the planet.\n\nThe Saturn Rings may contain water ice.\n\nWhat can be said with certainty is that both bound hydrogen and bound oxygen can be found on and around Saturn.
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Yes, Planets are generally spheres, not cubes or cylinders or odd shapes. Some small galactic bodies such as asteroids comets do have odd shapes, but planets, suns and stars and even moons look like spheres. That's because, when they were formed millions of years ago, they were essentially molten liquid.  Gravity and meniscus forces (surface tension) cause the object to take on a rounded shape--and it cools in that position.  In addition, the nature of gravity will pull uniformily toward the center--as the distance from the center increases, so does the gravitational force. You can think of gravity as a force that points inward toward the center of all things that have mass-- so that every part of the surface (especially liquids)is pulled evenly toward the center, resulting in a spherical shape.\n\nPlanets are not perfect spheres because there are other forces acting on the planets too which are trying to stretch them.  Because they were once hot moltent liquid, they buldge in the middle.  Earth and the moon reflect this phenomina.   Although gravity keeps planets close to spherical, there are other forces that cause deviations from the basic spherical shape. For example, the rotation of the earth once every 24 hours, causes an apparent centrifugal force which creates a bulge at the equator. In fact the earth's diameter at the equator is 7,926 miles while the diameter between the poles is only 7,900. \n\nNote that planets and moons had to be a liquid or they would not have been able to escape the gravitational force of the nearest larger body.  Remember that liquid will seek the path of least resistance as it moves.  In otherwords, an impact on the earth would cause a splash of moltent material that could escape the earth's atmosphere at the exact angle (path of least resistance) to be able to exit the planet's atmosphere without burning up.  Once it exits into space, the gravitational pull of the larger body will pull it into orbit. It will stay in orbit until it is acted upon by a larger force.   Fortunately, we haven't seen any larger forces since the earth was created and therefore, the conditions will remain for millions of years into the future.
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on Saturday, June 17, Mars and Saturn were\n"lined up" as seen from the Earth  - some might\nrefer to this as a collision, but it is not of course\npossible for them to actually collide, only to \nappear to do so in the sky.  Even then, the path\nof Mars took it just north of Saturn's placement\nin the sky... this is an event that occurs roughly\nevery two years, so is not so rare.  Much more\nrare is when Mars occults Saturn (Saturn\nactually disappears behind the disk of Mars)\nThe odds of that happening are extremely\nsmall, and I doubt if it would happen more\nthan once per thousand years...
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They have energy, and gravity depends on stress-energy not simply mass. However, the gravitational interaction would be exceedingly week.\n\nThey also polarise the vacuum state and so can scatter via the electrostatic interaction. This again would be a very tiny effect and has never been detected, though proposals for experiments exist - see link.
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The electrons are traveling at such speeds around the nucleus that they are always falling toward the nucleus as they orbit it. Picture the earth travelling around the Sun, to whose gravity it is attracted. It is moving about the Sun at a great enough speed that it doesn't collide with the Sun. But the Sun's gravity is great enough that the Earth doesn't fly off in a straight line.\n\nIf you swing a ball attached to a string around your head, its acceleration is toward the center (your hand) but its velocity is tangental to its orbit.\n\nThe same is true for electrons and protons. Because of the speed of the electrons, they travel in an orbit around the nucleus. But because of the attraction, the electrons don't fly off in a straight line.\n\nAsh's answer below is a little incorrect. The satellite IS attracted to the planet. That's why it doesn't fly off in a straight line. The gravity of the earth attracts the satellite, but the satellites velocity is in a straight line pointing the directio it WANTS to travel if it weren't for the earth's gravitational pull.
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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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Pluto, being both much smaller than Earth and less dense would have lower gravity.\n\nMars is also less dense, and is also considerably smaller, giving it a lower gravity.\n\nThe gas giants are (on average) less dense than Earth, but much much much bigger, and so have much higher gravity.  Saturn's average density is actually lower than that of water, but because there's so much of Saturn there, its gravity is quite high.  There's some sort of rule in schoolbooks about the solar system that they have to mention that Saturn could float in a bathtub, and that's what they mean.\n\nThe gravity of a planet is directly corellated to both its diameter and its density.\n\nFor example, the Earth is about 8000 miles across, and has a density of 5.5 (g/cc).  On Earth, acceleration due to gravity is 9.8 m/s2, also known as 1 G.  \n\nSaturn has a density of 0.7 (g/cc), but a diameter of 74500 miles.   Multiplying these together, and comparing to Earth's numbers, we discover that Saturn has about 1.185 times the acceleration due to gravity that Earth does.\n\nMars is 4200 miles across, and a density of 3.9 g/cc.  This comes out to a gravity 0.38 that of Earth.
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not really. To have planets and moons it has to have a gravitational pull
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The planets in our system are way, way too small to do anything like this. It would take something with the density of a black hole (or perhaps just a neutron star) to do something like this.
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some asteriods have gravity.billions of years ago,some rocks gathetred together to form the planets.when two asteroids colide to one,small particals are blast out but still controlled by the gravity of the astroid.when millions of astroids form to one,the small particalls get more.soon planets are born.but every planet dont have moons yet instead they have rings even earth.the small particalls eventually will collide again to form moons.even saturns ring will eventually form moons and you can see no rings
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Gravity is a very weak force.  Think of a fridge magnet.  A small magnet, or large for that matter, will stick to a fridge despite the gravity from the entire earth pulling it down.