Spotless Days

As of today, 26 August, 2009, the sun has not had a sunspot  for 47 days.  Since 1849, this is the 5th longest period without sunspots. If there are no sunspots in the next two days,  the new total of 49 will put this period in 4th place.   The number 1 period was 92 days long without a sunspot and that occurred in 1913.  See chart below for other long periods without sunspots.

The sun’s activity remains low with the 10.7 solar radio flux at 67. If you are unfamiliar with this measurement, the following from my entry   “Sun and Climate—an  Essay”  should help:

Another indicator of the Sun’s activity is the 10.7 cm (2800 MHz) radio flux.  This measurement is the amount of solar noise that is emitted by the sun at 10.7 cm wavelengths. Some consider it to be better than Sunspots as an indicator of solar activity.  The solar flux is measured and reported at approximately 1700 UT daily.   It can vary from values below 50 to values in excess of 300 (representing very low solar activity and high to very high solar activity respectively). Values in excess of 200 occur typically during the peak of the solar cycles.


Courtesy of Solaemon’s Spotless Days Page



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