The Sun at 19.5nm

Back


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 11:14 pm
Author: BrunoTheQuestionable

Length: 00:03:56
Rating: 4.79
Views: 296356

Tags: SOHO Sun FeXII 19.5nm astronomy

Video Comments:
Segagensis66 (October 11, 2008 at 7:05 pm)
Well don't go blind doing that lmfao
avatargir (October 9, 2008 at 10:57 pm)
The Sun is so beautiful. I stare at it everyday.
Sacarie13 (October 9, 2008 at 6:15 pm)
Sun is growing up into teenager she gonna have BF~ so sweet~!
LancerEvo007 (October 8, 2008 at 7:21 am)
So are we going to all die if Field is gone?????

Nuuuuuuuu I DUN WANNA DIE
thevestboy (October 8, 2008 at 7:29 am)
The magnetic field is the main barrier agains the solar winds/solar radiation. The field eminates from the poles which is where we get the north and south magnetic poles.
Some of the "winds" ride get passed and ride aling the magnetic lines and hit the earths atmosphere. This is when we get to see the aurora borealis
jigglehomes (October 7, 2008 at 6:42 am)
we're fuckt!
thevestboy (October 6, 2008 at 4:35 am)
If you can catch when the instabilities on the sun's surface blow you can see the highly charged particals blowing passed the view. It would look a bit like static. I can't remember when exactly, about 2002-2003 there was a solar mass ejection seen almost perfectly on the horizontal so 90 degrees from our perspective. I am with a weather explorers post and several experts in space weather analized it and said that if the ejection was pointed at Earth we would have been cooked.
thevestboy (October 6, 2008 at 4:40 am)
Some may say that the magnetic field of the earth would protect us from this, but the further south you see the aurora borealis the weaker the field is at the time. Solar radion is strong enough to flip some of the field lines to the opposite side of the planet. Our magnetic field would be too weak to take a direct hit straight on. Solar activity is also linked to magnetic field switches along with the earth. Hold on to your hats, the red on your compass might be pointing a different direction
waddingo (October 3, 2008 at 10:57 pm)
wow
djillali8722 (October 1, 2008 at 2:49 am)
what means that deference ?????