It appears the sun is heading into a deep magnetic cycle minimum. As most people are aware the number of accumulated spotless days during the solar cycle 23/24 transition is now the highest since 1914. Solar wind speed and density is the lowest since space measurements were taken. Curiously in addition to a reduction in the production of sunspots, the magnetic field strength of each new sunspot that is now produced is declining. The maximum magnetic field strength of a sunspot prior to the solar cycle 23/24 change was around 3000 Gauss. As the field strength of individual sunspots is reduced they can no longer be seen visually (The sunspot's magnetic field blocks energy transfer so a region of the sunspot is cooler which causes the sunspot to be darker than the general surface of the sun.) http://wattsupwiththat.files.wordpress.com/2009/06/livingston-penn-chesire_fig2.png This is an interesting article by the solar research scientists Livingston and Penn that discusses the observation and analysis related to the reduction in magnetic field strength in each new solar sunspot that is produced. http://wattsupwiththat.com/2009/06/...shire-cat-new-essay-from-livingston-and-penn/ Comment: The sun is of course the closest star. Somewhat surprising solar observations indicate that something may be incorrect fundamentally with the basic solar model and hence also with stellar models. Answering the simple questions as to what creates sunspots and the solar wind do not have an answer when the solar data is looked at in more detailed. For example, the mechanism hypothesized to create a sunspot must also explain why the sunspot magnetic field strength of individual sunspots can decay. The purpose of this thread is a repository for the data and analysis related to solar cycle 24 and some of the recent solar observational anomalies that are not explained by the standard solar models.