When you touch the wire to the terminal, allowing current to flow, the compass needle will twitch, registering the magnetic field you have created. Currents also flow in the sun. Although an ordinary atom is electrically neutral, the temperature inside the sun is hot enough to strip electrons off atoms, producing a stew of negatively charged electrons and positively charged atomic nuclei called a plasma. These plasmas boil like oatmeal in a pot, heated by the 15 million-degree nuclear hot plate deep in the core. As they rise toward the surface, they cool and begin to sink in a process called convection.
Convection currents take up nearly one-third of the outer portion of the sun.
By means still unknown, rivers of charged particles sometimes generate powerful magnetic fields that loop like gigantic ropes and sometimes push to the surface. When they emerge, they create sunspots. We see these as dark spots because intense magnetic fields stifle local convective flow of energy from the interior, making gases in the spots about 4,000 degrees Fahrenheit cooler than the surrounding solar surface, which is about 10,400 degrees. Sunspot fields become more or less numerous on a cycle that averages 11 years from a minimum of a few to a maximum of nearly 200. No one knows why it's that particular span of time.