Solar minimum

Solar minimum is the period of least solar activity in the 11 year solar cycle of the sun. During this time, sunspot and solar flare activity diminishes, and often does not occur for days at a time. The date of the minimum is described by a smoothed average over 12 months of sunspot activity, so identifying the date of the solar minimum usually can only happen 6 months after the minimum takes place. Solar minima are not generally correlated with changes in climate but recent studies have shown a correlation with regional weather patterns.

Solar minimum is contrasted with the solar maximum, where there may be hundreds of sunspots.

Solar minima and maxima are the two extremes of the sun's 11-year activity cycle. At a maximum, the sun is peppered with sunspots, solar flares erupt, and the sun hurls billion-ton clouds of electrified gas into space. It's a good time for sky watchers who enjoy auroras, but not so good for astronauts who have to be wary of radiation storms. Power outages, satellite malfunction and communication disruptions, and GPS receiver malfunctions are just a few of the things that can happen during a solar maximum.

At a solar minimum, there are fewer sunspots and solar flares subside. Sometimes, days or weeks go by without a spot. It is a safer time to travel through space, but a less interesting time to watch polar skies.

Their non-linear character makes predictions of solar activity very difficult. The solar minimum is characterized by a period of decreased solar activity with few, if any, sunspots. The accompanying decrease in solar radiation makes it the safest time for astronauts to carry out space missions. Three NASA scientists were better able to predict solar cycles (solar minima and solar maxima) using a simple function with four parameters, which then led the ability to discover the duration of these solar cycles. Scientists from the National Center for Atmospheric Research (NCAR) also developed a computer model of solar dynamics (Solar dynamo) for more accurate predictions and have confidence in the forecast based upon a series of test runs with the newly developed model simulating the strength of the past eight solar cycles with more than 98% accuracy. In hindsight the prediction proved to be wildly inaccurate and not representative of the observed sunspot numbers. .

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