why don't satellites fall to earth or float away into space?
how do they get it to keep its position. and circle the gloab without floating away or the earth pulling it in.
- Vinni and beerLv 71 decade agoFavorite Answer
Arthur C Clarke, the famous sci fi writer, first came up with the idea of geo-sychronous orbital satellites
satellites have to go at a speed such that the centrifugal force, exactly counterbalances the pull of gravity.
the lower the orbit, the faster the satellite has to go, to counteract the pull of gravity
low earth orbit satellites are used for mapping and weather/ geological info gathering
at a certain distance from earth, this speed is the same as the speed of rotation of the earth. If a satellite is launched into geo-synchronous orbit, it will always appear to be over the same spot on earth. these satellites are used for communication
- Kris LLv 71 decade ago
Gravity. While there is 'no gravity' in 'space' there is gravity with every 'body' in space ... suns, planets, asteroids, etc.
When we send the 'rocket' into space, they don't go 'far' ... and they stay up there with 'power' of some sort, frequently nuclear power, since that is both 'inexpensive' and lasts longer than a 'chemical' power. That 'power' keeps it in 'orbit' around the earth ... with the 'gravity' being what keeps it from 'floating off' into deep space.
Satellites do 'fall to earth' though, if they run out of 'power' ... and that frequently causes some people to 'worry' about getting hit on the head by falling pieces of satellites. That doesn't happen, for the most part, because things 'burn' from the friction and gasses in our atmosphere, and because there is far more 'water' on this planet than land.
This is a very 'basic' explanation, but it's a fairly good approximation in 'common English' of why satellites stay in orbit.
About how they 'stay in position' ... most have just enough power to keep them moving at a certain rate. If it is a 'geosynchronous' orbit, they 'move' at the same basic rate as the earth turns. If it's not a geosynchronous orbit, they move at a 'set rate' that is easily tracked by people on earth.
- yoyoLv 51 decade ago
They are in orbit - basically they are falling towards earth but at the same time are moving tangentially so never get any closer.
TV satellites are in geostationary orbit - ie they stay over the same spot. They can do this by orbiting at the same speed the earth rotates. All geostationery orbits have to be above the equator.
The altitude, weight and speed of satellites can change. Given two of these variables the other is fixed. So if you've built a satellite weighing a particular amount and want to orbit at a set height the speed of it is fixed.
- Anonymous1 decade ago
It is a finely calculated balance between the mass of the object ot satellite and it's distance from the earth. Close enough for the gravitational pull to stop it going into space, but far enough away for the gravity to be strong enough to cause it to fall back to earth. It falls into a safe permanent orbit.
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- Anonymous1 decade ago
A geosynchronous orbit is an orbit around the Earth that is at the same speed the earths rotation. Eventually the earths gravity will pull the satellite down where the atmosphere will burn it up.
- DarkskinnyboyLv 61 decade ago
Satellites don't fall to earth or float away into space because the scientists know how to keep them in orbit and knows how much force and rotation will be involved.
- ericbryce2Lv 71 decade ago
A satellite stays in orbit by a delicate balance between speed and gravity.
Let's say you had a very powerful gun and you shot it towards the east. If the bullet is moving fast and high enough it would not fall to Earth but continue to fall "around it". This concept is not an easy one to understand but it is the all to do with what is called orbital mechanics. It was not until about 50 years ago that mankind has been able to build and launch artificial satellites.
Satellites orbit high above our atmosphere which would slow them down because of friction. Even that high up there is still sufficient amount of air molecules of air to slow them down over a long period of time. If they slow down enough then the delicate balance between speed and gravity is upset and the satellite will fall to Earth.
- toryLv 41 decade ago
The Earth provides a gravitational pull, as well as other planets which keep the satellites suspended in their position. NASA, for example monitor these satellites and check for any interference or change to the satellites. There are also different orbits that the satellites could be in, a polar orbit, for instance.
- Anonymous7 years ago
Satellites do not fall to earth basically because of the gravity in space. Scientists calculate a specific altuitute and speed so satellites can maintain the equilibrium while they are in the vacuum :)
- morningfoxnorthLv 61 decade ago
Gravity keeps them close to the Earth, and their speed keeps them from falling.
For every satellite at some position and velocity, there is an orbit around the Earth. Most orbits don't hit the atmosphere, so they just keep going around the Earth.