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Post by lsvalgaard on Mar 4, 2011 13:57:11 GMT
af4ex- That was my assumption, but not knowing I did not expect the tilt to be so pronounced. My expectation was that it would be closer to the axial tilt of the earth at 23.4 degrees, but I guess if you add in curvature it can get you here. It could also be more pronounced because of atmospheric interference and the bending of light. You have to add the 7 degree tilt between the Earth's orbit and the Sun's equator. |
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Post by guigui1984 on Mar 4, 2011 14:09:24 GMT
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Post by af4ex on Mar 4, 2011 14:23:13 GMT
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bradk
Level 3 Rank
Posts: 199
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Post by bradk on Mar 4, 2011 15:13:27 GMT
Well, I guess I was seeing something impressive I was too uneducated to know it.
Over at WattsUpWithThat they are calling it a lunar eclipse...
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Post by af4ex on Mar 4, 2011 15:27:42 GMT
Well, I guess I was seeing something impressive I was too uneducated to know it. Over at WattsUpWithThat they are calling it a lunar eclipse... The correct term would be 'partial solar eclipse', but you're right, the arc is too tight for Earth. It is the Moon. Proba2 does get eclipsed by the Earth also. The last link I posted above refers to a "dual eclipse" movie observed from Proba2, 1) partial solar eclipse (also observable from the ground) and 2) 'Earth Eclipse' caused by Earth coming between Proba2 and the Moon (a kind of event never observed on Earth). Unfortunately that movie link seems to be stale. :-| |
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bradk
Level 3 Rank
Posts: 199
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Post by bradk on Mar 4, 2011 15:29:58 GMT
I had just assumed the SDO was at a LaGrange point
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Post by af4ex on Mar 4, 2011 15:42:48 GMT
bradk> I had just assumed the SDO was at a LaGrange point Oops, how did I think it was Proba2? Sorry about that. (Had cataract surgery on Tuesday and I guess my eyeball is still not seeing normally).
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Post by THEO BAKALEXIS on Mar 4, 2011 21:13:01 GMT
The last two days the region 11164 is the only area with activity. The region giving C-class flares yesterday and today. I make a closed view video with the activity of the region. www.solar-007.eu/site/ |
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Post by Kevin VE3EN on Mar 4, 2011 21:25:28 GMT
The last two days the region 11164 is the only area with activity. The region giving C-class flares yesterday and today. I make a closed view video with the activity of the region. www.solar-007.eu/site/Nice movie. |
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Post by france on Mar 4, 2011 22:18:45 GMT
We have a Solar Flux that has read above 100 for the first 4 days of the month. Today's reading of 121 is actually higher than last month's high of 125 which was contaminated by a flare. For the last several months one side of the Sun has been churning while the otherside is blank. What's even more interesting is the Northern Hemisphere has been very active while the Southern Hemisphere has sputterred repeatedly. Even when it looks like it's finally going to take-off it poops out. It is not unusual for the active hemisphere of the Sun to switch during the rise phase but there has been no indication of that thus far. I suspect that transition will occur during the peak which will be unusually broad because of the timing of this reversal. OK, like Dr Svalgaard says it's just the begining of the real rise. Today value is 127. I noticed the peak happened exactly one year after the last first peak on 2/12/2010. I don't understand very well why you speak about "the link between the timing of the reversal and the broad of the peak" |
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Post by Bob k6tr on Mar 5, 2011 0:37:16 GMT
Hi Leif I would like to revisit this post again with a few more questions. X-posted from WUWT: The polar fields have been changing of late. There are several points to make here: 1) because of the large pixel size [1/11 of the solar diameter] the polar fields measured at WSO will be seen to reverse about a year before they actually do. See paragraph [7] of www.leif.org/research/Cycle%2024%20Smallest%20100%20years.pdf2) the polar fields in the two polar caps are not strongly correlated, one can change a year or more before the other one. 3) the reversal is not a slow, regular progression, but proceeds in random jerks or ‘surges’ of opposite polarity moving towards the poles. On average there are about five such surges. obs.astro.ucla.edu/torsional.html4) the total polar flux is small, only a one thousandth of the sunspot flux [over the cycle]. 5) the past few months have seen a very powerful surge of positive polarity towards the north pole [but none so far towards the south]. Because the polar fields were already weak, this surge has completely cancelled the north polar fields, even to the point that the polar coronal hole that normally lives there has virtually disappeared. You can see that here: stereo-ssc.nascom.nasa.gov/beacon/beacon_secchi.shtml6) since we expect more surges in the year(s) to come it thus seems possible that the north polar fields might build to be stronger than they have been at this last minimum, thus presaging a large cycle 25. We don’t know this for sure, of course, but it seems very possible to me. This is somewhat unexpected, so, yes, these are interesting times Regarding point no 6 what is it about this surge in "New Magnetism" that leads you to believe the North Polar Field will build larger at solar minimum than what was experienced at the last Solar Minimum ? Is it because the surge was early ? Or was it's magnitude unexpectedly high ? It also appears that the Northern and Southern Hemispheres of the Sun are out of kilter as I have alluded in other posts. We are now 26 months after Solar Minimum and activity in the Southern can still be described as inconsistent while the Northern Hemisphere is chugging along. To me this would indicate one of two things. 1) The Magnetic Dynamo of the Southern Hemisphere is particularly weak or 2) Activity in the Southern Hemisphere is out of synchronization by a large margin. I tend to side with the latter because we saw Solar Activityin the final phase of Cycle 23 continue in the South for well over a year after activity had ceased in the Northern Hemisphere. This could have contributed in larger part to the extended Solar Minimum we experienced. So with that thrown out l would be pleased to have your reactions. Bob |
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Post by Bob k6tr on Mar 5, 2011 1:20:38 GMT
We have a Solar Flux that has read above 100 for the first 4 days of the month. Today's reading of 121 is actually higher than last month's high of 125 which was contaminated by a flare. For the last several months one side of the Sun has been churning while the otherside is blank. What's even more interesting is the Northern Hemisphere has been very active while the Southern Hemisphere has sputterred repeatedly. Even when it looks like it's finally going to take-off it poops out. It is not unusual for the active hemisphere of the Sun to switch during the rise phase but there has been no indication of that thus far. I suspect that transition will occur during the peak which will be unusually broad because of the timing of this reversal. OK, like Dr Svalgaard says it's just the begining of the real rise. Today value is 127. I noticed the peak happened exactly one year after the last first peak on 2/12/2010. I don't understand very well why you speak about "the link between the timing of the reversal and the broad of the peak" France there are a few items here. As I mentioned in the previous post we are now 26 months past Solar minimum. Big Cycles are short ones. Three of the largest Cycles in recent history are Cycle 22 which peaked at a SSN of 157 Spots, Cycle 21 which peaked at a SSN of 165 and Cycle 19 which peaked at a SSN of 200. The rise time for Cycle 19 was 30 months, the rise time for Cycle 21 was 40 months while the rise time for Cycle 22 was 27 months. Cycle 23 was an "Average Cycle" which had 2 peaks. The first peak occurred at 48 months while the second peak occurred at 70 months. Cycles with multiple peaks are not uncommon among average or weak cycles but never seen among big ones. Check out: www.solen.info/solar/cycl1_20.html . So it appears that at least one criterea for a big Solar Cycle is synchronization between the sun's northern and southern hemispheres. To say that we have now only entered the rapid rise portion of the cycle is to imply this cycle will be very long indeed. And if the peak does occur in May 2013, as many are predicting, that will mean the rise phase of Cycle 24 will last 53 months. I tend to disagree with Leif that Cycle 24 will follow the form of Cycle 14 which had 4 distinct peaks. But there will be 2 peaks much like Cycle 23 and the period between the 2 peaks will be equal to the lag factor of the Solar Southern Hemisphere meaning at least a year and possibly as long as 18 months. As to the SSN numbers at those peaks I don't have the foggiest idea. The harder I look the more muddy that picture becomes. |
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Post by lsvalgaard on Mar 5, 2011 1:43:39 GMT
Hi Leif I would like to revisit this post again with a few more questions. X-posted from WUWT: The polar fields have been changing of late. There are several points to make here: 1) because of the large pixel size [1/11 of the solar diameter] the polar fields measured at WSO will be seen to reverse about a year before they actually do. See paragraph [7] of www.leif.org/research/Cycle%2024%20Smallest%20100%20years.pdf2) the polar fields in the two polar caps are not strongly correlated, one can change a year or more before the other one. 3) the reversal is not a slow, regular progression, but proceeds in random jerks or ‘surges’ of opposite polarity moving towards the poles. On average there are about five such surges. obs.astro.ucla.edu/torsional.html4) the total polar flux is small, only a one thousandth of the sunspot flux [over the cycle]. 5) the past few months have seen a very powerful surge of positive polarity towards the north pole [but none so far towards the south]. Because the polar fields were already weak, this surge has completely cancelled the north polar fields, even to the point that the polar coronal hole that normally lives there has virtually disappeared. You can see that here: stereo-ssc.nascom.nasa.gov/beacon/beacon_secchi.shtml6) since we expect more surges in the year(s) to come it thus seems possible that the north polar fields might build to be stronger than they have been at this last minimum, thus presaging a large cycle 25. We don’t know this for sure, of course, but it seems very possible to me. This is somewhat unexpected, so, yes, these are interesting times Regarding point no 6 what is it about this surge in "New Magnetism" that leads you to believe the North Polar Field will build larger at solar minimum than what was experienced at the last Solar Minimum ? Is it because the surge was early ? Or was it's magnitude unexpectedly high ? It also appears that the Northern and Southern Hemispheres of the Sun are out of kilter as I have alluded in other posts. We are now 26 months after Solar Minimum and activity in the Southern can still be described as inconsistent while the Northern Hemisphere is chugging along. To me this would indicate one of two things. 1) The Magnetic Dynamo of the Southern Hemisphere is particularly weak or 2) Activity in the Southern Hemisphere is out of synchronization by a large margin. I tend to side with the latter because we saw Solar Activity continue in the South for well over a year after activity had ceased in the Northern Hemisphere. This could have contributed in larger part to the extended Solar Minimum we experienced. So with that thrown out l would be pleased to have your reactions. Bob Typically there are five to seven surges, the flux coming from the sunspot activity.  We have had most in the North, so no wonder the surge has reversed the North polar fields, but done little to the South Pole. As there, presumably, are several more surges to come, the North pole might build up a fair amount of flux [which is unexpected]. That the poles change polarity at different times is also typical, even when it was first observed: www.leif.org/EOS/Babcock1959.pdfNow, all this is wild speculation. |
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Post by sunspotboy on Mar 5, 2011 7:57:21 GMT
Dr Isvalgaard,
Where can I find the differences between the flips of South and North since 1957-1958?
Much appreciated!
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Post by france on Mar 5, 2011 14:57:36 GMT
dr Svalgaard wrote
do you mean flux will not up to 120/125 ?
So I understand when polarity reverse on pole, flux account will be about the same up to maximum ?
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