The Sun at 19.5nm

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SOHO observations of the Sun's outer atmosphere (FeXII at 19.5nm)

The level of solar activity goes through a cycle of maxima and minima with one cycle lasting roughly 11 years. In 1996 the Sun was around minimum, and in 2000 it reached maximum. In 2007 the Sun is again around minimum at the end of the cycle (no. 23).

The level of solar activity is matched by the number of sunspots on the Sun's surface. Sunspots are regions with an increased density of magnetic field lines that pass through the Sun's surface. Inside these regions, the surface is some 2000 degrees cooler than normal and therefore appears dark (in visible light), creating the distinctive appearance of sunspots.

Usually sunspots occur in pairs, with two sunspots of opposite sign as defined by the direction of the local magnetic field: N (outward magnetic field) and S (inward magnetic field). The relative position of the N (north) and S (south) sunspot is dependant on the pair's location on the Sun's surface and also changes with each solar cycle.

During cycle 23, on the Sun's northern hemisphere the orientation of all sunspot pairs is to have as leading and trailing spot the N and S spot, respectively, with respect to the Sun's rotation. On the southern hemisphere the orientation is reversed with the S spot leading and the N spot trailing.

With the next solar cycle this orientation is flipped in both hemispheres, as the Sun's global magnetic field reverses its orientation.

As a new cycle begins, the number of sunspots with the reverse orientation will increase and the ones with the orientation of the old cycle will decrease in number. In the transition period they can both occur on the Sun, as the two cycles have no sharp boundary and overlap.

SOHO constantly monitors the Sun and will continue to observe the evolution of the sunspots and the solar activity during the new solar cycle, which will culminate in the solar maximum in about 5.5 years time. Solar scientists predict that the upcoming solar maximum will be very active and could even be the most fierce in decades.

Channel: Science & Technology
Uploaded: October 4, 2006 at 4:14 pm
Author: BrunoTheQuestionable

Length: 00:03:56
Rating: 4.80
Views: 323389

Tags: SOHO Sun FeXII 19.5nm astronomy

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numbing numbered numerous Comments:
TuagVimKoj (December 5, 2008 at 11:06 am)
so .. wat i think that.. why the weather is changing so much throughout the years... like snow in spring and such.. the sun's been changing through out the years.... looking at this video it is scary.. alot of thoughts come to my mind when i saw this video... one could only wait and see what tomorrow will bring.
SlavkoDurko (December 5, 2008 at 8:44 am)
What the Hell is going on on the Sun?
yourwitness (December 4, 2008 at 6:39 pm)
i love the sun, and all stars, they have always interested me, but the only thing i can make of this in my mind is that the sun is...of course...running out of hydrogen, and in 6 billion years (earth time) the sun will explode into a super nova or collapse into itself and create a black hole... EGADS!
stradrools (December 4, 2008 at 7:37 am)
global warming is a fact but it is not because of the sun but because of the atmosphere in earth.
johnayerger13 (December 3, 2008 at 9:35 pm)
there's global warming! our sub in school was right!
sniggedi (December 3, 2008 at 4:00 pm)
Looking at this makes me feel so small. Shit, there's even stuff smaller than humans and bigger than the sun in an (theoretically) infinite universe.

Depressing, but beautiful nonetheless.
teemuruskeepaa (December 2, 2008 at 2:05 am)
I just read Durkheim who explained that religions are created by the community and its strong mutual feelings in rituals and cults that separate the mundane and sacred and create the symbols of the society.
jacobite19 (December 1, 2008 at 1:32 am)
Oh so it might not just be global warming... Lovly...
Dogwood14 (December 1, 2008 at 12:08 am)
ive been to sun
apedescent (November 30, 2008 at 3:38 pm)
If Dick's Belived in a God that God would look like a Dick.

If Pussy's Belived in a God that God would look like a Pussy.

If Asshole's Belived in a God that God would look like an Asshole,etc,etc,etc