Since all continents drift, and poles shift, what do scientists use as a "fixed point" on earth for GPS?
155316
all gps mesurements are based on a hypothetical mathematical approximation of the earth's surface called a geode. the "fixed" point is a mathematical abstraction.
405952
Ask around if any of your friends have a GPS system.  There is your example of a daily-life example of the theory of relativity.  The Global Positioning System would not be able to give you very accurate locations if it did not take the corrections to time and distance from both special, and general reletivity into account.  I am pretty sure that it is the first piece of public consumer-grade equiptment that relies on our understanding of General Relativity.
124364
Well, in these days we can use satellite technology to map the globe, by getting information from both geological & geographical satellites, and combine that with GPS technology, you will get what you seek.
1053820
Stationary in reference to what fixed point?
166937
check out http://www.answers.com/center%20of%20earth
849157
Zero As the north pole . IT is only a point. Do youwant instead superficy of Antarctica?\n\nif you see my link 14.2 millions km^2
124708
I like this site for looking at where the continents were at different times as the forces of plate tectonics (continental drift) occured.\nhttp://www.scotese.com/earth.htm\n\n50MYA: http://www.scotese.com/newpage9.htm\n150MYA: http://www.scotese.com/late1.htm\n\nThey even project into the 250MY into the future:\nhttp://www.scotese.com/future2.htm\n\nThey also animate the movement of the plates:\nhttp://www.scotese.com/newpage13.htm
135108
It will pretty much look the same. Normal plate techtonics\nmoves continents very very slowly and you need more then a\nthousand year window to see any real difference. Just look\nat maps from the year 1006 if you don't believe me.
1132574
check this out:\n\nhttp://gpsinformation.net/
194469
There are three types of North to consider.\n\nMagnetic north is determined by the Earth's magnetic field. This point moves considerably wandering in an eliptical path on a daily basis, and moves even more over a period of decades. On average it moves 10 km per year. Because of this all maps require a correction to be made for the reading of a compass in order to match the map. This is known as declination, also called magnetic declination. Declination also varies according to variations in the Earth's magnetic field in different geographic areas.  In order to use a magnetic compass to navigate with a map you must know your local declination value. \n\nTrue north is determined by the celestial North pole, which is the term used by navigators for the position of the star Polaris. This point will only be useful for about another thousand years because of the precession of the Earth during its orbit. Precession could be described as a wobble in the Earth's axis of rotation. \n\nCelestial north, or grid north is the point where the earth's spin axis hypothetically extends through the earth. Relative to our position on the planet this does not change because it is essentially an arbitrary point decided on by cartographers. However it is not consistent from one geographic coordinate system to another. This is because a globe is the only way to accurately represent all points on the earth and a map using any two dimensional coordinate system will have errors in some part of the map.
1046996
Any consumer electronic device containing microchips relies on quantum physics for the diodes and transistors on the chips to work.   The laser in a CD player relies on quantum physics for its operation.   The Global Positioning System depends on very precise timing of satellite radio signals.   A special relativity correction is applied to allow for the motion of the satellite relative to you, and a general relativity correction because you are deeper in the Earth's gravitational potential well than the satellite.   Time passes at a different rate for the satellite than for us.   If these corrections were switched off, your GPS navigator would become less accurate.
824576
a globe should have the lat and long markings on them and lines that follow them.\nyou can also use google earth and scroll around until you hit that.
798191
To get a good GPS fix you need to receive signals from several satellites at large angular separations from each other, along the dimension that you're trying to get a fix for.  If all the GPS satellites were in geosynchronous orbits (and therefore in the plane of the equator) there would never be much separation in the north-south direction, so you couldn't get a good latitude fix.  Even the longitude fix would be poor (compared to the present configuration), since the satellites would not have quite as much east-west separation (as seen from the US, for example).  This separation problem exists even in the current system when you try to determine altitude with GPS.  Since all the visible satellites are "up" and none are "down," the altitude determination is a lot less accurate than the determination of latitude or longitude.
175308
No. Directions like north, east, south, and west are only imaginary "points" on earth, created by humans. Its only purpose is to provide us with a sense of navigation.\n\nA compass works on polarity. It is only one pole of a magnet being attracted by another pole of another magnet. Luckily for us, there is a location called "Magnetic North", not far from the North Pole. This location has polarity, which attracts the needle of a compass.\n\nIf you go to outer space, the compass will most likely not point north, depending on how far you are from earth. The compass will only point to the magnetic pole which has the greatest influence on it. If you are near earth, the compass will point to Magnetic North, but if you are farther away, another magnetic pole will most likely attract the compass, and it will point in that direction.\n\nHope I could help you...
868199
Countries on the southern hemisphere. Think about the tilting earth as it orbits. Australia would be a good example.
950044
In high-energy physics, medical treatments, and space detections, quadrupole field distributions and sextupole field distributions are often required over a large spherical volume. Traditionally, these fields can be generated with cylindrical magnets. In comparison with cylindrical magnets, the spherical magnets have the advantages of smaller values of inductances, lower energy storage, and less magnetic flux leakage. The basic method derives from the target field approach that has been used to solve many of the inverse electromagnetic problems. \n\nCalculation:\n\nThe geomagnetic poles or geocentric dipole, can be computed from the first three Gauss coefficients from a main field model, such as the WMM or IGRF. Based on the current WMM model, the 2005 location of the geomagnetic north pole is 79.74°N and 71.78°W and the geomagnetic south pole is 79.74°S and 108.22°E. \n\nThe magnetic poles or dip pole are computed from all the Gauss coefficients using an iterative method. Based on the current WMM model, the 2005 location of the north magnetic pole is 83.21°N and 118.32°W and the south magnetic pole is 64.53°S and 137.86°E.\n\nThe location of the center of the eccentric dipole, sometimes known as the magnetic center, computed using the first eight Gauss coefficients for 2005.0, is at approximately (r, φ´, λ) = (552 km, 22.2°N, 141.6°E). \n\nThe task of locating the principal magnetic pole by instrument is difficult for many reasons; the large area over which the dip or inclination (I) is nearly 90 degrees, the pole areas are not fixed points, but move tens to hundreds of kilometers because of daily variations and magnetic storms, and finally, the polar areas are relatively inaccessible to survey crews (map of North and South polar wander - courtesy of Dr. John Quinn, U.S. Geological Survey retired). The Geological Survey of Canada keeps track of the North Magnetic Pole, which is slowly drifting across the Canadian Arctic, by periodically carrying out magnetic surveys to redetermine the Pole's location. The most recent survey, completed in May, 2001, determined an updated position for the Pole and established that it is moving approximately northwest at 40 km per year.
623360
greenwich england is zero long and the equator is zero lat\n\nhttp://www.satsig.net/maps/lat-long-finder.htm