Why does the moon stay in orbit around the earth instead of falling into orbit round the sun?

Question

Its for a GCSE physics project so relatively basic terms, or explained complex terms where necessary would be preferable!

Answer 1

The distance ratio of 1/243,000, versus 1/93,000,000 miles is the reason that the mutual attraction of the earth-moon system keeps them together. Gravitational attraction if governed by the inverse-squares law. As a result, distance is a greater factor than the huge mass of the sun in this case.
Both objects follow a wobbling course around the sun alternately catching up with each other and then falling behind. The 'orbit' of the two is actually the path of the center of gravity of the combined system. The paths of the two bodies look a little like two snakes climbing a tree, with the moon making bigger deflections because of its lower mass.The moon's orbit looks like a circle, (more or less), around the earth because we are on one of the objects involved in the combined motion.

Answer 2

you have quite often figured this out wisely your self. The Earth is a lot closer to the Moon than is the sunlight, so it has a lots superior gravitational consequence. somewhat, the Moon DOES orbit the sunlight, in a very wobbly line. you ought to think of of it because of the fact the Moon orbiting the sunlight and then being pushed and pulled by making use of the Earth so as that its course is nearly a sine wave. the enlargement of the universe is barely appropriate on the very best scales, between galaxies and communities of galaxies. At close selection, gravity is a lot extra effectual. This explains why galaxies many times collide with one yet another. even although the universe as an entire is increasing, gravity can pull close galaxies mutually so that they collide and have interaction.

Answer 3

EDIT: My first answer was wrong. The sun's effect is actualy stronger than the earth's even at it's great distance. Here's the real reason:

"Because the Moon is in orbit around the Sun (as well as in orbit around the Earth). Another way of looking at it is that the center of gravity of the Earth-Moon system is revolving around the Sun, and the Earth and the Moon are revolving around their common center of gravity. The Sun is pulling on the Moon, but the Earth is "falling" right along with it, so they stay together"

http://helios.gsfc.nasa.gov/qa_earth.html#ugc

I had worked up some quick calculations and the earth's mass is 320,000 times smaller than sun, but 465 times closer. Square that and you get the sun's gravity is 216,225 less than ours (from distance alone, exclusding mass). But that is less than the difference in mass, so the sun actually has more pull than us.


I'm glad you asked that question!!

Answer 4

Because gravitational attraction goes as the distance between the objects squared. So if you're 10 feet away instead of 5 feet away, the pull of gravity is 1/4th as strong. The Earth is much closer to the Moon than the Sun is, and thus has a much stronger pull on it.

Answer 5

Please look at the theory of Moon's evaluations. It is supposed to have come out of Earth itself. When it came out, the speed and mass of this part was such it could not escape from the gravitational force of Earth. As per another theory Moon was captured by Earth when it was heading into our solar system. Earth captured Moon as moon's speed was less than Earth's escape velocity at that distance. Yet Sun could have pulled Moon from Earth if Sun were to have more G force than Earth. You can calculate the force of gravity of Sun and Earth on Moon considering the mass and distance of of these objects from the formula: product of masses of two objects divided by square of distance between those objects with respect to Earth - Moon and with respect to Sun and Moon. When you compare this you will find the G force on Moon by Earth was nearly thrice to that of Sun on Moon. You can calculate yourself.
Some more info: The Moon is considered as satellite of Earth for convenience. In reality it is also a planet. Earth and Moon form binary planets. They are considered as so because the center of moons orbit does not coincide with that of Earth. Normally the center of binary planets would be some where in the space between the two planets. But here it falls with in the Earth. So it is referred to as Satellite.

Answer 6

Because gravity is inversely proportional to the square of the distance, and the Earth is much closer than the Sun, so the force of attraction is stronger.

Answer 7

Because the moon is close enough to the earth -- and far enough from the sun -- that earth's gravity is stronger on the moon than the sun's.

Answer 8

The moon is in orbit around the sun, it orbits the sun every 365 1/4 days just as we do.

Answer 9

The gravity produced by the Earth is weaker than that produced by the sun...but the Earth is a lot closer, which gives it an advantage.

Answer 10

I believe that is due to the gravitational pull of the earth. The same forces that keep us from popping off into outer space as the world turns. Simple enough?