An enery source for Mars, Moons and Asteroids

[nexium]

The magnetic field of the sun is moving fast, but very weak at Mars. Will a large voltage be produce from one end to the other of any conductor on the surface of Mars? Is there any practical way to use this as an energy source? Neil

 

[Aetius]

I'd think that the localized regional magnetic fields on Mars probably keep out the Sun's magnetic field.<br /><br />On Phobos and Deimos, you could probably use electrodynamic tethers to generate electricity from the solar magnetic field, but it would create drag.<br /><br />Phobos is gonna smack into Mars in another 50 million years, but I don't want to rush things along with a giant power-generating tether. <img src="/images/icons/wink.gif" />

 

[Boris_Badenov]

Atomic Reactors powerful enough to run Aircraft Carriers & safe enough for 5000 people to live within 1000 feet of for months at a time are available right now. <br />What need is there for exotic power sources that require magnitudes of extra effort just to access when a reactor can be parked a few hundred feet away from your base & you can just run an extension cord to it? <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>

 

[billslugg]

The interplanetary magnetic field at earth distance is 1 to 37 nT, with an average value of ~6 nT. At Mar's distance it would average about 3 nT.<br /><br />Faraday's Law gives the voltage induced in a wire sweeping through a magnetic field.<br /><br />V = B x A<br />V = voltage<br />B = field strength in Teslas<br />A = area swept by the wire in meters^2/sec<br /><br />The orbital speed of Mars is 25km/sec or 25,000 m/sec<br /><br />Suppose we laid out a 100km wire on the surface of Mars.<br /><br />V = 3x10^-9 Tesla x 25000 m/sec x 100,000 m = 7.5 volts.<br /><br />The problem is that the return wire generates the same voltage, thus no current flows. If you ran the return wire around the opposite side of Mars, then the field strength there would be a bit weaker, thus some net voltage would be generated thus some current would flow.<br /><br />Another strategy would be to wind a coil from pole to pole and use the spinning of Mars to generate a voltage, ignoring the speed it revolves around the sun. The diameter of Mars is 6700 km. The average radius of the coil would be 1/4 that or 1700 km. Circumference is 5000 km. Speed is 60 meters/sec. Swept length of coil is 2D or 13,400 km. <br /><br />V = 3x10^-9 Tesla x 60 m/s x 13,400,000 m = 2.4 volts. <br /><br />One circum-Mars coil would produce 2.4 volts. If it was made out of #2 copper (1/4 inch diameter) the resistance would be .16 Ohm/kft. A coil around Mars would be 22000kft or 3500 Ohms. A short circuited coil would flow with .6 milliamp of current at 2.7 volts producing 1.6 milliwatts of power - all of which would be dissipated as heat. If we could make the coil out of superconducting metal then that power would be ours to use. A million turns of wire around the planet would produce 1600 Watts of power.<br /><br />Lemons with nails in them would be a better bet. <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>

 

[dragon04]

The absence of a significant magnetic field around Mars makes it problematic as there's essentially no difference in potential to be had in terms of electromagnetic energy.<br /><br /> <div class="Discussion_UserSignature"> <em>"2012.. Year of the Dragon!! Get on the Dragon Wagon!".</em> </div>

 

[nexium]

So I suppose 100,000 meters of wire (in a straight line) above Earth's atmosphere would produce 7,500,000 volts, if moving 25,000 meters per sec across a 3 millitesla magnetic field. That is one million times stronger field, and 3 times orbital speed at 1000? km altitude. If the loop impedance is 75,000 ohms, 100 amps would flow? Apparently the loop is completed though the very thin ions at this altitude? Does the average speed of near by ions increase significantly, because of the fast moving wire? Is the reported arc of a high speed tether propaganda = disinformation = lie? Perhaps the arc was not produced magnetically? Neil

 

[billslugg]

neil<br /><br />100,000 m of wire moving 25 km/s through a field of 3 milliTesla would produce 7.5 million Volts. <br /><br />But where do you get 25 km/s? Leo speed is 7.5 km/s.<br />Where do you get 3 milliTesla? Solar magnetic field at Earth is 6 nano Tesla. Earth's magnetic field is about 30 micro-Tesla.<br /><br />100,000 meters of wire moving 7.5 km/s through the Earth's magnetic field would produce a voltage of 100,000 x 7500 m/s x 30x10^-6 or 22,500 V.<br /><br />I believe that the cable is coaxial. The return line is inside the sheath and thus does not see the magnetic field. The voltage at the bottom of the cable must have been enough to jump the insulation. <br /> <div class="Discussion_UserSignature"> <p> </p><p> </p> </div>