Solar Phenomenons: The Sun, Sunspots, and Current Sunspot Activity
Sunspots are a phenomena that occur on the surface of the sun and can bee seen as dark spots against the brighter surface. They are very transient in nature – meaning they don’t last very long and change shape rapidly.
Sunspots are caused by intense magnetic activity on the surface of the sun, which inhibits convection or the movement of solar material from the hot center of the sun to the surface. Since convection is slowed in areas of sunspots, the region becomes cooler and less bright. The interesting thing is that despite the fact that sunspots appear dark on the solar surface, if you were to look at one without the brightness of the surrounding photosphere, it would actually be brighter than an electric arc!
Sunspots change shape and have been know to shrink and expand rapidly over the course of a few days. They can also be quite large – up to 50,000 miles in diameter which is plenty big to be seen without a telescope from earth. As a result, observations have been recorded for hundreds of years. This has led scientists to discover a pattern. The number of sunspots increases and decreases over a period of about 11 years. When the number of sunspots observed is high it is called solar maximum and when there are no sunspots observed, it is called solar minimum. We are just emerging from a period of solar minimum and the number of sunspots is increasing. According to Nasa, solar maximum is expected to peak in May of 2013.
Now before you run outside and start staring at the sun read the rest of this post! Staring at the sun with the naked eye is not good. Do not do this! You will permanetly damage your retina! Suggested ways of viewing the sun include using dark filter glass like a welder’s glass or by using a telescope eyepiece to project the image directly onto a piece of white paper. If you ask me, though, the most amazing place to see incredible images of the sun and to learn more about our nearest star is Nasa’s Solar Dynamics Observatory or SDO. Check it out!