What produces the magnetic field in the Sun?

Mostly the flow of plasma - plasma is the fourth state of matter, a hot gas where electrons and atomic nuclei separate, so when you have convection flows inside the sun, this automatically means that you have moving electrical charges, which produces a magnetic field.

The full interaction is a bit more complex, stronger magnetic fields can actually even block convection flows, which is then the cause of the colder sun spots. Or the magnetic field can be amplified by plasma taking it with it, even deep into the solar system.

What Produces A Magnetic Field

The Moon has NO magnetic field, so astronauts leave their compasses home. The Sun's magnetic field is related in a complex manner with sunspots, coronal mass ejections, flares, and some other solar phenomena, a few of which have some effects on Earth, such as interfering with radio and TV. The only things expected to happen in 2012 are the summer olympics, and the election for President, neither of which much depends on the Sun or the Moon.

Since the Earth's magnetic field is produced by the molten metal core of the Earth, I'd say the magnetic field of the Sun is produced by the molten metals (and maybe even the gases) active on the Sun and which the Sun is made of.

The magnetic field of the Earth is caused by a solid inner iron core at the center surrounded by a liquid iron outer core. The liquid outer core rotates at a slightly different speed than the solid iron core and that causes our magnetic field. The Sun is not fully understood but would dare to suggest that the process is similar.

The charged particles is what causes the magnetic fields on and in and around the sun.

The insanely high pressure and temperature of the hydrogen in the interior of the Sun gives it metallic properties, substituting nicely for the molten iron core at the center of Earth (the source of our own magnetic field). The same thing goes for the gas giants.