“since fusion is at the sun’s surface”

Since your other two inquiries were answered I thought I would ask about these remarks. Where did you gather this information. I have to question whether this is some kind of joke, perhaps some theory I’m unfamiliar with, or you simply do not know what you are talking about. Forgive me if I seem rude, it is not my intention.

More on topic, since it is cooling and shrinking will/when it collapse and implode? Or maybe just remain a dense ball of metals?

The Earth is thought to have a magnetic field because of its liquid outer core, made of iron and nickel. According to dynamo theory this conductive liquid is “stirred” by the Earth’s rotation, which generates an electric field. That in turn generates a magnetic field.

You can’t believe everything you read on Wikipedia, but it’s a good place to start:
http://en.wikipedia.org/wiki/Earth_core#core
http://en.wikipedia.org/wiki/Dynamo_theory

I thought all planets had a solid core, as most were originally comets that have been captured into our solar system, & then developed into planets.

Wouldn’t the sun have more influence on Mercury re the magnetic field?

Perhaps especially so, since fusion is at the sun’s surface?

Regards,
Christina