Re: Could we raise orbit thru magnetorque?
All,
So why is the maglev principle (magnetic levitation) http://www.google.be/search?hl=nl&q=maglev&meta= not applicable in space?
Magnetic levitation applied to trains generates an upward force equal and opposite to the earth's gravitation.
BR, -- //\arc
-----Original Message----- From: amsat-bb-bounces@amsat.org [mailto:amsat-bb-bounces@amsat.org] On Behalf Of Bruce Bostwick Sent: Wednesday, February 21, 2007 6:51 PM To: amsat-bb@amsat.org Subject: [amsat-bb] Re: Could we raise orbit thru magnetorque?
That's been my understanding as well. Magnetorquing by itself can drive rotation but not translation. Its main benefit is that it saves propellant, weight, and complexity, as well as moving parts and the risk of a hypergolic plumbing assembly exploding and taking out half the spacecraft's systems, by allowing the spacecraft to handle rotation with more reliable torquing coils and get its energy for that from the PV panels. Changing orbits still requires firing a reaction thruster of some sort.
On Feb 20, 2007, at 9:47 AM, John Mock KD6PAG wrote:
Argument is: if when satellite is in the north, a north magnetic field is applied on z plane, will satellite raise orbit ? Same but opposite on south. Considering limited energy available could this raise be significant if applied on all orbits ?.
I believe magnetorquing can only change the orientation of a satellite and not its orbit. It is certainly used in the process of changing an orbit, in order to get a thrusting device pointing in a direction where it will do something useful. But by itself, it can't change an orbit. It can help point antennas in the proper direction, etc.
-- KD6PAG (Networking Old-Timer, Satellite QRPer)
"People don't like to be meddled with. We tell them what to do, what to think, don't run, don't walk. We're in their homes and in their heads and we haven't the right. We're meddlesome." -- River Tam, "Serenity"
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All,
So why is the maglev principle (magnetic levitation) http://www.google.be/search?hl=nl&q=maglev&meta= not applicable in space?
Magnetic levitation applied to trains generates an upward force equal and opposite to the earth's gravitation.
BR,
There are no steel rails up in the sky... ;-)
-jari oh3uw
At 05:55 AM 2/22/2007, Marc Vermeersch wrote:
All,
So why is the maglev principle (magnetic levitation) http://www.google.be/search?hl=nl&q=maglev&meta= not applicable in space?
Magnetic levitation applied to trains generates an upward force equal and opposite to the earth's gravitation.
Much larger (relative) difference in separation between the pole pairs that are repelling each other. One pair (top of the track and bottom of the train) are almost touching, the other ends of the fields are much more widely separated.
In the case of a satellite around the Earth, the difference in separation is almost zero (width of the satellite, compared to the distance from the satellite to the Earth's magnetic poles). The gradient of the Earth's magnetic field is quite small, even near the magnetic poles. You could get a very small lift by orienting the satellite correctly and turning on the magnetic field as it passes over the poles, but the effect would be incredibly tiny, and holding the orientation would take another system, to prevent the system providing torque instead of thrust (if that uses fuel, then the exercise is pointless ;) ), and if it's magnetic, it could nullify the thrust from the magnetic thruster.
73 de VK3JED http://vkradio.com
I think the trick is to use a switchable magnetic monopole, rather than a dipole. I think I have a can of some that I savaged a few years ago. Got them from some odd junk I found in a corn circle. I'm sure they're lying somewhere in the shack.
Sil
participants (4)
-
Jari -
Marc Vermeersch -
Sil - ZL2CIA -
Tony Langdon