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bloodhound31
28-06-2007, 07:53 PM
I have noticed that all the sunspots I have seen, seem to revolve around the sun in about the same place and time periods. Can anyone explain? I thought Sunspots were random and could appear anywhere as the magnetic bands play havoc with the surface. It looks to me like its the same sunspot going around and around repeatedly. It does change a little in shape and size, but looks like a permanent fixture.

Hmmmm?

Baz.:D

iceman
29-06-2007, 04:58 AM
The sunspots do rotate with the rotation of the Sun, and the same sunspot can appear in subsequent rotations, but that's generally a rare condition rather than the rule. If it's a really large sunspot you can certainly see it again when it rotates around to face us again.

We've been in solar minimum, so the number of sunspots has been very small. We're approaching solar maximum in the next few years, so you'll start seeing more and more sunspots in many different locations.

CoombellKid
29-06-2007, 07:53 AM
I'm at home today, and with no jet stream present... wahooooo!!!! . I think
I'll get out the solar scopes and have a gander at o'l sol

regards,CS

Dujon
29-06-2007, 11:17 AM
Hello, Baz,

Yes, as Mike says, you can see sunspots re-emerge, though it's not a given as many are short-lived. The sun rotates relative to the Earth around and about every 25 days. So for nearly a fortnight any given sunspot is out of view. Most sunspots don't last that long.

As far as the positioning of sunspots is concerned they seem to move in an approximately eleven to twelve year cycle (as we see them). During this time they tend to move towards the poles and their frequency decreases. I don't mean individually, just the latitude of their appearance. At this point in time we are at a 'low' sunspot cycle - meaning that there are not many of them. Over the next few years (five to six if predictions hold true) you will see many more sunspots most of which will appear close to the Sun's equator.

okiscopey
29-06-2007, 01:52 PM
Baz, it's all to do with butterflies apparently! See graph at:

http://www.windows.ucar.edu/tour/link=/sun/activity/butterfly.html

rumples riot
29-06-2007, 03:09 PM
As far as anyone can tell at present we are yet to emerge from cycle 23 and start cycle 24. There were some hints late last year with some spots switching polarity, but it seems that there have been no high latitude spots with reversed polarity at this stage. The reversal of polarity indicates the switch in magnitism and the change of the cycle. The current thinking is that next year cycle 24 will commence near mid year with it peaking at maximum around 2012. At present solar activity is really at a very low ebb. We will see some spots continue and some of older spots reimerge from the depths of the solar converyor belt.