Spotless Sun: Blankest Year of the Space Age
10.06.08
Astronomers who count sunspots have announced that 2008 is now the "blankest year" of the Space Age.
As of Sept. 27, 2008, the sun had been blank, i.e., had no visible sunspots, on 200 days of the year. To find a year with more blank suns, you have to go back to 1954, three years before the launch of Sputnik, when the sun was blank 241 times.
"Sunspot counts are at a 50-year low," says solar physicist David Hathaway of the NASA Marshall Space Flight Center. "We're experiencing a deep minimum of the solar cycle."
A spotless day looks like this (below left):
Left: A photo of the sun taken Sept. 27, 2008. The face of the sun is "blank," i.e., completely unmarked by spots.
Right: The sun on Sept. 27, 2001. The sun's face is peppered with colossal sunspots, all crackling with solar flares.
Credit: ESA/NASA Solar and Heliospheric Observatory (SOHO)
Top: A histogram showing the blankest years of the last half-century. The vertical axis is a count of spotless days in each year. The bar for 2008, which was updated on Sept. 27th, is still growing.
Bottom: A histogram showing the blankest years of the last century. As in the above histogram, the bar for 2008 is still growing.