Sunspots 1026 and1027 are members of new Solar Cycle 24. Photo credit: SOHO/MDI
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What is the sunspot number?
Updated 22 Sept 2009
Spotless Days
Current Stretch: 0 days
2009 total: 212 days (80%)
Since 2004: 723 days
Typical Solar Min: 485 days
During 2008-2009 NASA scientists noted that the Sun is undergoing a "deep solar minimum," stating: "There were no sunspots observed on 266 of [2008's] 366 days (73%). To find a year with more blank suns, you have to go all the way back to 1913, which had 311 spotless days: plot. Prompted by these numbers, some observers suggested that the solar cycle had hit bottom in 2008. Maybe not. Sunspot counts for 2009 have dropped even lower. As of September 14th, there were no sunspots on 206 of the year's 257 days (80%). It adds up to one inescapable conclusion: "We're experiencing a very deep solar minimum," says solar physicist Dean Pesnell of the Goddard Space Flight Center. "This is the quietest sun we've seen in almost a century," agrees sunspot expert David Hathaway of the National Space Science and Technology Center NASA/Marshall Space Flight Center [3]. It's a natural part of the sunspot cycle, discovered by German astronomer Heinrich Schwabe in the mid-1800s [4].A "clockwork pattern" that has held true for more than 200 years
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