There Goes the Sun

Has anybody found the remote for the Sun yet? Its output is now lower than it has been at any point since 1913.

The idea of the Solar cycle dates back less than 200 years, though it stems from discoveries made in the 17th century. Bear with me: Galileo started observing the Sun around 1610 and discovered sunspots. He also went blind -- don't stare at the Sun, okay?

Anyway, in the 19th century some stereotypically methodical German astronomers, Samuel Schwabe and Rudolf Wolf, began counting sunspots and analyzing their frequency. They discovered something kind of neat: sunspots go in an 11-year cycle. Every 11 years the number of sunspots drops off to nearly zero, then starts building up again.

Right now we're in the middle of an unusually long sunspot minimum. What does this mean? Well, in good news it means less heating of the upper atmosphere, less radio interference, less solar flare risk to astronauts, and in general a quieter environment in space. On the other hand, it might plunge the Earth into an ice age. Plus no auroras.

What exactly causes this cycle is not well understood. Obviously it has something to do with how the Sun's core produced energy, or how the Sun's outer layers release that energy, but as one might imagine it's hard to study the interior of a star.

In the meantime, if you do run across the remote, turn the power back on.