Are there any terrestrial worlds (planets or moons) with dynamo cores like Earth?

Question

A dynamo requires requires 3 things: conductivity, rotation, and convection. Earth's core meets these criteria and therefore produces a magnetic field which protects us from cosmic radiation.

Venus has a magnetic field but only due to the processes of its atmosphere, not its core. Its core is thought to be conductive and even though it rotates slowly simulations show it should produce a magnetic field. So, Venus's core most likely lacks convection (most likely caused by the lack of plate tectonics keeping the core molten).

Mars's dynamo shut down around 4 billion years ago after its core cooled too much. This allowed solar winds to blow away Mars's atmosphere leaving it the underpressurized desert it is today.

I was wondering if any other terrestrial worlds produce a substantial magnetic field due to a dynamo core like Earth.

I doubt mercury. All other terrestrial world are moons. Do any of them have magnetic field seperate of the planet they orbit?

Info was from wikipedia.

Answer 1

Yeah, why not? The universe is huge!

Answer 2

Mercury does have a global magnetic field.  It's not as strong as Earth's.  Mercury does not have much atmosphere.  They call it an exosphere, because individual atoms and molecules don't interact much, and more or less follow ballistic courses.

The MESSENGER space craft confirmed the magnetic field in it's Mercury flyby recently.  The magnetic field was discovered by Mariner 10.

Answer 3

um ok well lets see mr science guy im kinda thinking that there is no other planet lyk earth cuz if there was there would be plants on it an there would be a big scene about it on da news so ya laterz =]

Answer 4

No. The Earth is very special planet: It have the dynamo core, with the magnetic shield to protect our atmosphere. It have (the only one) the tectonic plate to produce the continent. It have a 23 grades axis tilt to increase the biosphere area.  The rotation is 24 hours, and that's very good.

As you said, Venus rotation is so slow that the magnetic field is very weak, and the day and night need very long time. The same is for Mercury.

I think: the Earth is a miracle (special edition) planet and we must take care of it.

The giant planets (like Jupiter) have a strong magnetic field, but it is due to the metallic Hydrogen and fast rotation.