When the Sun Lost its Spots – 25th March 2004

In “When the Sun Lost its Spots“, Tony Sizer first gave us some basic solar observing tips, went on to explain the main solar features that can be observed, with simple descriptions of the probable physical processes involved. Having described the series of observations that led first to the discovery of the 22 year solar cycle and then to the identification (first by Maunder) of the period of solar inactivity between 1645 and 1715 that’s now called the Manuder Minimum, he then took a diversion through the fields of archaeological dating using carbon-14 and tree-ring counting, before bringing us back to the not entirely comfortable realisation that the Sun is quite noticably variable, and that this variability has had significant effects on the Earth’s climate at several stages even in historical times. At present the Sun is very active but it is likely that it will become quiet again some day.