Global Positioning system means the a sytem to help you know your postion on a globle as in LATITUDE and LONGITUDE and its best activity is carried out in USA.
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There are three Global Positioning Systems in orbit at the moment, one from the U.S., one from Russia, and one from Europe. The U.S. one has been there the longest, so is the one most people know about.\n\nA complete GPS "constellation" is around 30 satellites all orbiting the world, each of them continually transmitting the current time VERY accurately. Your GPS receiver receives the time from different satellites at different times, so can tell that satellite A is closer than satellite B. With 4 satellites, the receiver can calculate its position relative to those satellites.\n\nImagine standing in a large field, with a drummer at each corner holding a different sized drum. Each drummer is beating their drum once a second at exactly the same time. If you stand near one drummer, you can hear that drum before any others, so you know you're closer to that drum. And you know which drum it is by the sound of the drum. If you're VERY good, and can time the differences between the drum beats, you can calculate where you are in the field. In this example, the drummers are the satellites and your ear is the GPS receiver.\n\nNote also that the GPS receiver does NOT transmit to the satellites at any time, just like you don't talk to any of the drummers.
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The Hafele-Keating experiment, though contested, holds up with the physics behind it. In fact, the global positioning system (GPS) in programmed with equations to compensate for the effect of time-dilation caused by the difference in in the gravitational field between the earth's surface and satellite orbit.
7020
Yes. Nearly the entire world and all of the scientific community use the metric system. In order to foster the idea of globalism in the US we should unify our measurements.
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G. UNITED STATES (USA)
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First question, yes.   GPS provides a location in three dimensional space, therefore your receiver can determine your elevation in relation to sea level if equipped (most are).  For best accuracy, you will need at least a 4 satellite position fix...with good satellite geometry (i.e. all the satellites are not lined up in a row in the sky).\n\nSecond question, in theory yes.   Technically, the answer is likely no.  The reason is that GPS signals are very weak by their nature and it requires a sensitive receiver to "hear" them.  While most receivers on the market today will be able to receive signals through tree leaves and other minor obstructions of the sky, the vast majority cannot not receive signals through concrete.  To demonstrate this, just take a walk with your GPS unit underneath an overpass and watch what happens to the signal strength.  \n\nIf you were measuring altitude inside, a barometric altimeter might be a better choice, though be wary of the building's ventilation system, as most are slightly pressurized and would affect this instrument as well.
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The main advantage is a somewhat "fixed" location in the sky relative to the Earth, and relative ease in repositioning them into other fixed positions. There are also some advantages to lower orbits. \n\nGPS satellites are NOT geostationary.  They rely on precise on board time signals and precise knowledge of their orbital ephemerii and a large enough "constellation" such that 3 or more are above the horizon and able for your receiver to pick up at any point in time over nearly the whole planet. \n\nWith a sophisticated control system you can make do with several low orbiting satellites.  The advantage with a low orbit is they are cheaper to launch, and can cover a broader range of latitudes ( geostationary orbits MUST orbit over the equator to be geostationary.  That means at higher latitudes they are lower on the horizon.  At some point they become unusuable, so are not suitable for high bandwidth or reliable communications in places like northern Europe or Russia.) Geo satellites would make EXCELLENT relay satellites for constellations of lower orbiting spacecraft, permitting spacecraft to spacecraft communication. Instead of having to relay between several to get around the globe (*) You could go up to a geo, over to another geo and back down to the other low orbiter and get almost anywhere.  You might need two hops between geos in some circumstances.\n\n(*)which would also require a much more densly populated constellation.  Iridium was named that because the original plan was to have as many satellites as the element Iridium has electrons; 77!
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It provides jobs and pays taxes to the states in operates in...and to the the USA as well. It also contributes to the economy of the other countries it operates in as well.
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Geographic information can give hints about the country's recources, economy, and even culture. You can use the geographical information to find trends in the country and use that to improve many aspects the developing country. It also allows you to prevent any negative aspects caused by location.
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A database with the longitudes/latititudes of almost every place on earth can be found here. I suppose you do know where you were born.\n\nhttp://www.heavens-above.com/countries.asp#P
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It means "for your information".
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you can look over the world.\nDemis:\nhttp://www.demis.nl/home/pages/home.htm
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google maps! maps.google.com Satellite view too!
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My guess is that they would still work-you would not get an accurate reading of your position though-what coordinate system or projection is space in? and the reading would have to bounce back into earth from a reading station and then back to the GPS units-\nWhich brings up another question? Would signals be lost in translation?\nI really don't know\nBut its gonna bother me.
37567
He's right. Google Earth and a screen capture program.
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googleearth.com it's very cool.
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a compass tells you which way is north. once you know where north is you can tell in which directions south, east, and west is.
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gpsstore.com ---search here and you will find one.