- Diamond Member
- Posts: 11439
- Joined: 01 Sep 2008, 20:13
- Location: 1770 Agnes Water Central Queensland
The Sun is a spinning ball of gas large enough to contain 1.3 million Earths. Its core is a furnace of nuclear fusion, converting 655 million tons of hydrogen into helium every second at a temperature of 28 million degrees Fahrenheit. This fusion creates energy that ultimately reaches us as sunlight. But the core and inner layers of the Sun are so dense that it may take a million years for a photon of the energy to fight just two-thirds of the way out. There it reaches what solar physicists call the “convective zone.” Above that is a thin layer we perceive as the Sun’s surface. Solar gases continue far into space beyond this visible edge in a blazing hot atmosphere called the corona. A tenuous solar wind blows through the entire solar system.
Things get especially interesting in the convective zone. Giant gyres of charged gas rise and fall, as in a pot of boiling water, only more turbulent. The Sun rotates at different speeds—about once every 24 days at its equator and more slowly, about every 30 days, at its poles. This difference in velocity shears the gas and tangles its electrical currents, fueling the Sun’s magnetic fields. The overall magnetic field has a direction, just as Earth’s north and south poles attract our compasses. However, the Sun’s field is full of curves and kinks, and every 11 years, it flips: the north pole becomes the south, then back to north again 11 years later. It’s a dynamic cycle that scientists don’t fully grasp, and it’s at the heart of most efforts to understand how the Sun behaves.
By Robert Irion Smithsonian magazine April 2011.
Read more: http://www.smithsonianmag.com/science-n ... z1kWG2fkPd
George Bernard Shaw
- Diamond Member
- Posts: 61895
- Joined: 22 May 2006, 15:29
- Location: Adelaide South Australia
- Emerald Member
- Posts: 6892
- Joined: 08 Mar 2010, 12:21
- Location: Northern Gold Coast, Australia
... and scientists still do not fully grasp the Sun's effect on Earth's weather (or that of other space phenomena).grandduke wrote: [ Snip ]It’s a dynamic cycle that scientists don’t fully grasp, and it’s at the heart of most efforts to understand how the Sun behaves.
[ Snip ]
There is a lot of interesting stuff on SpaceWeather.Com too ... particularly the Aurora Gallery pics:
http://spaceweather.com/aurora/gallery_ ... li666kkut5