does the earths magnetic field vary with altitude? <br />if so.......then is the magnetic flux experienced at higher altitudes less or more than that at sea level?<br />kindly suggest a reason for the same.........
nik_gr8test_rulz<br /><br />Welcome to SDC! <br /><br />Yes, the magnitude and direction of the earth's magnetic field varies with altitude as well as location.<br />In general, the field strength decreases with height. The strength of electric and magnetic fields generally fall off as the square of the increase in distance. <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>
The Wiki article covers all the high points.<br /><br /> Earth's magnetic field <br /><br /> This article contains some really good diagrams & more info not covered by the Wiki article. <div class="Discussion_UserSignature"> <font color="#993300"><span class="body"><font size="2" color="#3366ff"><div align="center">. </div><div align="center">Never roll in the mud with a pig. You'll both get dirty & the pig likes it.</div></font></span></font> </div>
Great references, Boris. Thanks! <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>
Since it is thought that the magnetic field is produced mostly 5000 kilometers below the surface, an altitude increase of 50 kilometers (1%) should produce a 10% decrease in magnetic field strength. Occasionally this is the amount we measure, but variations in magnetite just below the surface can produce larger variations, especially within a few meter of the surface. We likely have extensive, but clasified data on magnetic field at various altitudes for missile tracking purposes, even though the magnetic compass is rarely used for navigation now that GPS is available cheap. Before GPS, we had loran and lorac which were also far more accurate than a compass. Neil