Tomorrow we'll investigate the dark spots that now appear in the photosphere. The face of the sun, called the photosphere, is now dotted by many dark blemishes. These have the creative name sunspots. They are caused by magnetic fields in the gasses below them. Strong magnetic fields actually cool the gas causing sunspots to be darker than the rest of the photosphere.
Sunspots actually occur in groups.
In those groups, huge explosions can also occur. These are called solar flares, and are occasionally visible in white light. Astronomers usually view them through special filters that pass only the light of the element hydrogen. Flares spew protons and other charged particles into space causing coronal mass ejections that can affect the earth. More on the suns corona Thursday, but tomorrow we take our weekly look at the planets.