If the earth, the moon, or the sun weighs a vast amount, why is it floating in space?

Question

It's fascinating that objects that are so massive seem to hover effortlessly in space. If something the mass of the sun was placed on earth, what would happen? Does gravity cause it to sink to the earth's center? Can gravity explain why everything floats around in weightless space relative to each other?

Sorry for the multi-part question. I will award a best answer to anyone who best answers any one of these questions. Thanks!

Answer 1

The sun is a lot bigger than the earth (a million times bigger) so you couldn't exactly place it on the earth, but you could place it next to it. It would be like placing an apple on a grain of sand.

The sun is much more massive than the earth. The force that each would feel is the same, and depends on the product of the masses, but the acceleration of each body would would be different.

For example, when you fall out of a tree, you and the earth pull on each other and accelerate towards each other. However, you accelerate at 9.8m/s/s and the earth accelerates at basically 0.

Therefore, if the sun and the earth were placed next to each other, the earth would fall towards the centre of the sun. The sun basically wouldn't fall at all, except an infinitessimal amount.


Gravity actually explains why things *don't* just float in space. The space shuttle looks and feels like it is floating when you are in it or close to it, but it is whizzing around the planet at a high speed. Gravity is accelerating it downwards, but it is going so fast that the earth keeps curving away from it. It is in orbit.

The same principle keeps the moon 'floating' around the earth and the earth 'floating' around the sun. They really aren't floating at all, but falling, at just the right speed!

Answer 2

Gravity is created by mass. If something has mass, it has gravity, which is relative to its mass. In space there is no independant source of gravity. So there is nothing to pull objects down or up, just towards other objects.

If something the mass of the Sun was placed on Earth, its gravitional forces would rip the Earth apart, and add it to its own mass. The size of the object would affect how this happened (size of sun or a black hole), but the end result would be the same. Without any other outside forces acting on it, the object with the mass of the Sun would barely change position, while the Earth would be destroyed. Imagine the effect a bowling ball would have on a small, small pebble, if they collided, the bowling ball would barely notice the pebble.

Gravity is a part of why there are objects in space that 'float' relative to each other. In nebular clouds, where the dust is the densist, the gravity is stronger and this attracts more dust, eventually a star is born. The area nearby is free from dust. Meanwhile nearly all the objects in the sky are revolving around something... the sun, another planet, the galactic center (which our sun does). Orbits is a combination of gravity pulling the smaller object closer, and the smaller objects momentum causes it to keep going. The net effect is that it is 'falling' continuosly around the larger object.

Astronauts in the shuttle are actually orbiting the Earth, they are falling around the planet. Since in this situation, their rate of fall is constant - they appear weightless. The only astronauts that have been more independant of Earth's gravity are those that were traveling TO the moon. On the moon, they were still orbiting the Earth (on the moon), and on the way home they used Earths gravity to pull them home.

I know this may have answered more than you asked, but I hope it helps.

Answer 3

The earth, moon and the sun attracts each other with gravitational force. Think , if your two friends pull your two hands from two sides by same force, you will be steady. If this pull is from the every side of you, up,down, left, right, front and back is same, then you will be steady at a fixed place even you need not a solid space and you can float in vacuum,

In the same way, the stars and the planets are attracting each other. But as the forces is not same, they move with respect to other.
The system is so large that man can not imagine. The forces between trillion trillion stars and planet and other things in space is like a huge net in space. One stands/floats because of others. But the whole system does not stands or float on anything. It is in free space. As the free space cannot attract the system, there is no impact of free space on earth. Or , you can say that The Al-mighty hold the total universe.

Answer 4

Nothing is motionless, everything has motion. Earth and the Sun have nowhere to "fall". The sun exerts gravity attraction on the earth, the earth, being in motion, would fly off into space except that the gravity balances the centrifugal force and holds it in orbit. Everything is falling--just another word for being in motion. The speeds are enormous. I think the earth moves at something like 1500 miles an hour, you can probably google the exact speed. We are in an arm of the Milky Way Galaxy, which is turning, too, at a super astonishing rate of speed, and it is held from flying off into nothingness by the gravity attraction of the mass of stars and evidently also a super massive black hole at the center of this galaxy.

Answer 5

There's no attractive force in space like there is on the Earth. Nothing is pulling the planets down or up or sideways - but gravity keeps them in stable orbits as long as they maintain the same velocity.

If the Sun were placed on Earth, it would suck the Earth into itself since the Sun is so much more massive and large than the Earth and it's not a solid.

Answer 6

The question of why atoms attract one another is still not understood. The goal is to combine gravity, electromagnetism and strong and weak nuclear forces into a single unified theory.

The general theory of relativity addresses the problem of gravity and that of nonuniform, or accelerated, motion. In one of his famous thought-experiments, Einstein showed that it is not possible to distinguish between an inertial frame of reference in a gravitational field and an accelerated frame of reference. That is, an observer in a closed space capsule who found himself pressing down on his seat could not tell whether he and the capsule were at rest in a gravitational field, or whether he and the capsule were undergoing acceleration. From this principle of equivalence, Einstein moved to a geometric interpretation of gravitation. The presence of mass or concentrated energy causes a local curvature in the space-time continuum. This curvature is such that the inertial paths of bodies are no longer straight lines but some form of curved (orbital) path, and this acceleration is what is called gravitation.

Answer 7

"It merely looks hysterical to me that something ought to glide around in area that long with out having nailed by ability of an asteroid or something." Um...you comprehend what gravity is, genuine? You do have faith in that? and you have some theory of ways huge area is? Earth has been "nailed" by ability of a lot of asteroids. merely no longer a huge sufficient one to smash it. "I propose over those billions and billions of years, how do you comprehend that the carbon isnt being laid low with something?" as a results of fact we've a theory for a fashion carbon behaves, and so far no one has controlled to locate it behaving in a distinctive way. on no account. no longer even slightly. in case you think of carbon's behaviour isn't in actuality predictable and consistent, surely it is going to no longer be _that_ complicated to plot an test the place it does not persist with the guidelines which carbon relationship demands? All you ought to locate is _one case_ the place the guidelines do no longer artwork. Off you bypass.

Answer 8

Imagine the universe as gigantic mattress. Objects we put on the mattress (Planets/Stars), "sink" farther down, causing a slope. Hence, smaller objects "Roll" towards the larger ones. (IE gravity

Answer 9

compare the solar system with atom , electrons revolve round the nucleus as planets round the sun .Both atoms and electrons revolve with a constant speed hence develop centripetal force and continue to move in a fixed orbit hence they can never fall

Answer 10

Because the "great one" put them on fishing line.