The production of s planetary magnetic field requires?

Question

a) high planetary mass
b) atleast one satellite
c) an atmosphere
d) rotatione) a ring around the planet

Answer 1

Of all the answers you have there, d) is the most correct.
A molten core helps, but is not necessary, as Jupiter likely has no molten core - just metallic hydrogen.

Answer 2

Dynamo theories are generally used to explain planetary magnetic fields. Still one does not need rotation, since a magnetic field can be "frozen" into the minerals of the planet as it cools, including its core. This is why Mercury, although probably solid, and essentially not rotating (I believe it is in a 3/2 rotational resonance with its orbit) has a pretty hefty field.

I suppose rotation in the planet's past is likely necessary to drive the initial field that gets frozen in, however I challenge you to hypothesize a planetary formation mechanism that DOESN'T result in something that is rotating fairly quickly at first, so "d" is not a useful predictor of magnetic field strength!

Answer 3

That which causes a planet's gravitational field is its spin. As the energy of rotation moves from each pole toward the equator, they are found to be moving in opposite direction in relation to each other. When they meet at the equator, the energy of spin passing through that plane forms an electric field through the plasma. Magnetic fields form at a right angle to the electric one. The opposite motion of the energy fields (Coriolis Effect) give rise to the opposite poles of our planet. Planet Venus, almost our twin, has almost no rotation and almost no magnetic field. Planet Mercury has a magnetic field that is about 1 percent of ours.

Answer 4

e) none of the above: A spinning core of a Multan ferrous material.

Answer 5

d