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Of Late, Fewer Sunspots Than Usual

esocid writes "The sun has been laying low for the past couple of years, producing no sunspots and giving a break to satellites. Periods of inactivity are normal for the sun, but this period has gone on longer than usual. The sun usually operates on an 11-year cycle with maximum activity occurring in the middle of the cycle. The last cycle reached its peak in 2001 and is believed to be just ending now, with the next cycle just beginning and expected to reach its peak sometime around 2012. Today's sun, however, is as inactive as it was two years ago, and scientists aren't sure why. In the past, solar physicists observed that the sun once went 50 years without producing sunspots, coinciding with a little ice age on Earth that lasted from 1650 to 1700." (More below.) esocid continues: "The Hinode, a Japanese satellite mission with the US and UK as partners, has three telescopes that together show how changes on the sun's surface spread through the solar atmosphere. It orbits 431 miles (694 km) above the Earth, crossing both poles and making one lap every 95 minutes, giving Hinode an uninterrupted view of the sun for several months out of the year. Scientists are not extremely worried, but have added extra ground stations in case of interference from extra solar activity, and are ready for the Sun to resume its activity." (The Little Ice Age is fascinating, full stop.)

1 of 628 comments (clear)

  1. Re:solar warming, that's why. by mh1997 · · Score: 5, Interesting

    "...while the warming of Jupiter can be explained by increases in solar output, the warming of Earth can not.
    At least 25% of it can be:

    From http://www.sciencedaily.com/releases/2008/05/080512120523.htm

    Over the past century, Earth's average temperature has increased by approximately 0.6 degrees Celsius (1.1 degrees Fahrenheit). Solar heating accounts for about 0.15 C, or 25 percent, of this change, according to computer modeling results published by NASA Goddard Institute for Space Studies researcher David Rind in 2004.

    "Right now, we are in between major ice ages, in a period that has been called the Holocene," said Cahalan. "Over recent decades, however, we have moved into a human-dominated climate that some have termed the Anthropocene. The major change in Earth's climate is now really dominated by human activity, which has never happened before."

    My question is what is the optimum temperature to sustain life on our planet? I've searched and can't find that answer and would appreciate any help. I'm not denying warming or trying to flame, I am serious about the question.