The importance of the solar cycle predictions is nowadays completely understood if we consider the factors that Space weather affect. Planning for satellite orbits and space missions often require the knowledge of solar activity years in advance to ensure the safety of the instruments and the astronauts. Just for the history we have to mention that Nasa will always remember the solar storm of August 1972 because it occurred between two Apollo missions. The crew of Apollo 16 had returned to Earth in April and the crew of Apollo 17 was preparing for a moon landing in December. Even thought the radiation dose inside the spaceship would not be lethal the astronauts who have been hypothetically outside of the spaceship might have absorbed 400 rem radiation lever not necessarily deadly but a quick trip back to Earth for medical care would be necessary.
    As for the last solar cycle predictions, we all remember the past predictions two or three years before. Past model predictions had indicated a major magnitude increase for the sunspot cycle 24. On the other hand new predictions mention that the new solar cycle will be extremely quiet compared to the last one. The new solar cycle have a starting time of October 2008 with minimum occurring in November or December 2008 and maximum in June 2013 with a maximum sunspot number of about 70 ± 18 or less for cycle 24. Past predictions  of 2007 predicted a start at March 2008 and peak in late 2011 or mid-2012. Half of the predictions showed a moderately strong cycle of 140±20 sunspots expected to peak in October of 2011 and the other half predicts a moderately weak cycle of 90±10 sunspots peaking in August of 2012.
More info according to the models used: http://solarscience.msfc.nasa.gov/predict.shtml



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