ASTR 110G Chapter Notes - Chapter 15.2: Magnetogram, Heinrich Schwabe, Stellar Magnetic Field
Document Summary
Before the invention of the telescopes, the sun was thought to be an unchanging and perfect sphere. We now know that the sun is in a perpetual state of change: its surface is a seething, bubbling cauldron of hot gas. Vast plumes of gas erupt into the chromosphere and corona. Occasionally, there are even giant explosions on the sun that send enormous streamers of charged particles and energy hurtling toward earth. When they arrive, these can cause power outages and other serious effects on our planet. The first evidence that the sun changes came from studies of sunspots, which are large, dark features seen on the surface of the sun caused by increases magnetic activity. They look darker because the spots are typically at a temperature of about 3800 k, whereas the bright regions that surround them are at about 5800 k.
