How satellites runs for a longer time without getting any fuel? From where it gets the enrgy for orbiting?
449374
All of them have a source of power (usually solar cells) and batteries for storage.\n\nArrays of solar cells provide power to charge rechargeable batteries. Newer designs include the use of fuel cells. Power on most satellites is precious and very limited. Nuclear power has been used on space probes to other planets. Power systems are constantly monitored, and data on power and all other onboard systems is sent to Earth stations in the form of telemetry signals.
151403
Orbits are stable. If you have a little rocket in orbit and you suddenly jetteson the boosters, the boosters will stay in orbit even though you're not using them. The only reason objects eventually fall back to earth and burn up in the atmosphere is the atmosphere itself. The (very very tiny amount of) air friction the orbiting object is exposed to slows the oblect down. This lowers the altitude slightly, exposing the object to even more resistance. This is a runaway affect, causing the object to eventually fall out of the sky.\nOh, for your first question: Not counting junk, the earth posseses 1 natural sattelite (the Moon) and thousands of artifical sattelites (for TV, GPS, phone, etc.). Counting junk, the number extends into the billions. That's right, I said billions - that's not a typo of millions.
973904
I presume you mean the external fuel tank?\nIt is jettisoned just before the shuttle reaches orbit, and the tank lacking just a bit of speed to actually make it in orbit, it falls back and burns up in the atmosphere.
111919
Fuel-burning action-reaction is here to stay for a long time.  We don't know enough about gravity and space-time to manipulate it.
811878
HI \n      \n              YOUR QUESTION IS PLACEMENT OF SATELLITE AROUND THE EARTH. BEFORE GOING IN DETAIL YOU NEED TO UNDERSTAND GRAVITY. GRAVITY IS THE MAGNETISM OF EARTH THAT TRY TO ATTRACT ANY OBJECT NEAR THE EARTH WEATHER IT IS ON THE EARTH OR IN THE SPACE.\n       BECAUSE OF GRAVITY ONLY MOON KEEPS CIRCULATING THE EARTH.\n       \n            IN NORMAL PHYSICS RULES SAYS ANY OBJECT IN SPACE HAS ATTRACTION TOWARDS EACH OTHER, AND IT IS INVERSELY PROPORTIONAL TO THE SQUARE OF DISTANCE BETWEEN THEM.AND EQUALLY  PROPORTIONAL TO THE MASS OF THEM     \n      \n             SO NOW WHEN ANY SATELLITE IS READY TO BE LAUNCHED THEN IT WILL BE CALCULATED ACCORDING TO THEIR MASS SO THEY GET PERFECT DISTANCE. SO WITH SPACE CRAFT NOT THIS SATELLITE WOULD BEEN TAKEN TO SUITABLE DISTANCE AND BY USE OF ROBOTIC HAND IT WILL BE LAUNCHED IN IN SPACE, ONCE IT GETS IN ORBIT OPEN UPS ITS WINGS WHICH TAKES SOLAR ENERGY FOR MAKE THEIR PARTS TO BE WORKED.\n         \n           NOW OTHER RULE OF PHYSICS WILL WORK HERE THAT UNLESS AND UNTIL ANY EXTERNAL FORCE INTERACT WITH ITS MOTION NONE OF THE BODY WILL CHANGE ITS DIRECTION. SO SATELLITE KEEPS ON CIRCULATING AROUND EARTH LIKE MOON AND WORKS ON SOLAR ENERGY.
421726
I assume that by the question you mean "What keeps the satellite in orbit?".  It is a balancing act. Gravity is trying to pull the satellite back to Earth. The velocity of the satellite exactly counteracts the pull of gravity and in effect the satellite is falling around the Earth instead of falling to the Earth. \n\nThe speed of the satellite dictates the height of the orbit. There is exactly one height for a satellite that falls around the Earth at exactly the same speed that the Earth rotates--35,786 km. Communication satellite reside at the orbit so that they are always above the area of the globe with which they are used to communicate. \n\n What eventually happens to many satellites is that the friction of the wisps of atmosphere that the satellites transverse tends to slow them down. When that happens, gravity takes control and pulls the satellite back to Earth. Skylab was a good example of that happening.
313099
Well, it's literally "rocket science."  Gravity is the worst problem, probably.  It takes a huge amount of rocket fuel to get even a small object into space, let alone people and all the things they have to carry with them. (Imagine how exhausting it would be climbing straight up a 50-mile-high cliff.  Now imagine doing it without anything to hold onto!)  So once you get something up there, there's not much fuel left to keep accelerating.  Every little ounce has to be counted and allowed for in order to get a rocket up into orbit.\n\nBesides, in space everything is relative.  Spaceships and probes actually travel quite fast -- thousands of miles an hour -- but the places we're going to are MILLIONS of miles away.  The Cassini probe to Jupiter traveled nearly two billion miles to get there!\n\nFuel is just one of many problems that have to be dealt with in space travel.  In space, there is NOTHING at all.  No food, no water, no electricity, no heat, no air, no gravity.  Compared to space, walking across the Sahara Desert would be a fun hike.\n\nThere are so many things that you might never think of.  For instance, when the very first astronauts went into space, nobody knew what would happen to their eyes.  It was possible that in zero gravity their eyeballs would lose shape, and they would be blind!  Luckily, that didn't happen, but at the time nobody knew for sure.  Because of that and many other dangers, astronauts are very brave people.
605786
When a spacecraft is in orbit it needs no energy. That's the simple answer. However, you need to get it into orbit in the first place, and this means accelerating the object to the speed it needs to orbit the earth - around 18,000 mph. How much energy you need then depends on the mass of the object or spacecraft - this can be calculated from 1/2 mv^2. \n\nTo escape the earths gravity altogether the spacecraft needs to go faster, about 25,000 mph or 7 miles per second. So if you were going to Mars for example, once you achieve that speed you need no more energy.
144357
A radio relay station in orbit above the earth that receives, amplifies and redirects analog and digital signals contained within a carrier frequency. There are three kinds. Geostationary (GEO) satellites are in orbit 22,282 miles above the earth and rotate with the earth, thus appearing stationary. The downlink from GEOs back to earth can be localized into small areas or cover as much as a third of the earth's surface.\n\nLow-earth orbit (LEO) satellites reside no more than 1,000 miles above the earth and revolve around the globe every couple of hours. They are only in view for a few minutes, and multiple LEOs are required to maintain continuous coverage. Medium-earth orbit (MEO) satellites are in the middle, taking about six hours to orbit the earth and in view for a couple of hours.\n\nI hope this helps...\n\nDon
76096
Generally no. The orbiting debris is actually very little and very small stuff. Most items have decaying orbits that eventually burn up in the atmosphere. The launch window is when the earth's launch sight is in the proper alignment with the sun, moon, or other planets so that it can establish orbit and then leave earth's orbit in an efficient trajectory. \n\nMainly if you want to send a mission to Mars, you actually lauch so that the probe lets Mars catch it, instead of trying to attain enough speed so it catches Mars. This is more efficient and requires less fuel. \n\nThink of a rocket like a semi that has one ton payload, but it has to carry all the fuel to drive from New York to San Francisco. That's pretty inefficent. If the semi could instead use much less fuel and say start at New York, but remain stationary and let the earth rotate underneath it, then it would use much less fuel to reach its destination.
60264
Our moon is locked in what is known as a geo-synchronous orbit. For millions of years the angular momentum has stablized the moon to provide very little loss of energy between earth and moon. This does not account for the influences that the moon has upon our oceans though. (Tides) Our solar system has "moved about" for many millions of years to allow for efficient energy transfers between baryonic masses.  This is not unlike a person who sit's in a chair and move's about to become more comfortable.  Peace
932043
There is a very short "window" of opportunity to blast off, because they must do it when the earth is pointed in the trajectory they want the space craft to fly in. (the earth rotates)\nThey could blast off at any time but do not have enough capacity to store fuel to then change trajectory and get back on course.
167518
The energy of a satellite orbit is constant, energy defined as the sum of potential energy and kintetic energy (E = PE + KE).\n\nIn a circular orbit, both altitude and velocity are constant.  This means that the potential energy (PE) and the kintetic energy (KE) of the orbit are both constant, so there is no change in either potential energy or kinetic energy.\n\nIn an elliptical orbit, the satellite is constantly changing it's altitude, resulting in a transfer between KE and PE, even though total energy stays constant.  \n\nWork is defined as the difference between PE (or KE) at different points in the orbit.  Since the PE and KE are constantly changing, there is always work being done on a satellite in orbit.
592132
There's no oxygen in space but we all breathe. The sun has enough gravity to keep the oxygen inside it just like Earth but even more so. However this oxygen isn't for burning like we would burn wood. It is part of the cycle of nuclear reactions going on in the sun. The gravity of the sun is large enough to keep the mass of gas concentrated enough to be able to sustain such nuclear reactions.
3702
Old satellites contribute a lot to the pollution around our planet. A snippet from the article below,\n\nAlthough penetration of space by people and their machines is but a few decades old, already the space above the Earth has become contaminated. There are now 110,000 man-made objects larger than a half-inch orbiting in the space above the Earth, and the situation has gotten so serious that NASA 'now replaces pitted orbiter windows after most flights' of space shuttles, notes a 1987 US National Research Council report that warns of potentially catastrophic collisions with space debris. The amount of 'space junk' has doubled since 1990 and now poses 'a navigational hazard,' says Norwegian space specialist Erik Tandberg. The US and Norway are planning a giant radar station to be called Globus II in Norway's Arctic specifically to better monitor orbiting debris.\n\n'A total of over 3,000 tons of space debris surrounds the Earth today,' says Dr. Alexey Yablokov, a noted biologist and president of the Centre for Russian Environmental Policy. The 'rapid accumulation of debris' could 'complicate the further development of astronautics since there would be a direct threat of collision with debris fragments which travel at very high altitudes,' says Dr. Yablokov.\n\nAmong the junk now overhead are 37 nuclear-powered satellites put in space by the US and former Soviet Union. The operation of the satellites is over but the radioactive fuel in them is still hot and lethal and they'll be falling back to Earth in the centuries ahead.
962875
The speed of the satellite changes in an elliptical orbit. It slows as it approches the farthest part of the orbit and speeds up as it leaves the farther parts and comes closer to the planet. When it speeds up, its kinetic energy is increasing. For its kinetic energy to increase, work must have been done.
78131
Right now there isn't much. The idea of nuclear power for spacecraft isn't too attractive, given the radiation, fallout, and potential mess after an accident. \n\nThe old chemical rockets have experienced an upgrade recently, thanks to the Russian technology of the closed cycle motor. The energy used to run the pumps used to be jettisoned outside the motor bell, but the Russians needed that extra bit of power for their N1 moon ship, and designed the NK33 closed cycle motor. Thankfully, some of the motors survived the cold war, and ended up in the hands of researchers who used them to construct the closed cycle motors that power the Atlas 5. The New Horizons spacecraft rode out on the Atlas 5, which was the fastest launch in history. The Apollo ships took three days to cover the distance between Earth and Moon; New Horizons did it in 9 hours. That's an improvement.