|
|
Post by lsvalgaard on Sept 8, 2011 5:16:43 GMT
Question on axial tilt of the sun: It's about 7 degrees from the ecliptic. In what season of the earth does the northern hemisphere of the sun face most towards the earth? Also, since sunspots and CME's are not equal across the equator, do we have seasons of events depending on this? Does the solar wind have seasons based on tilt? In September [today, in fact!]. The tilt is so small that there is no significant dependence on the tilt. CMEs are typically 40-50 degrees wide. |
|
|
|
Post by Bob k6tr on Sept 13, 2011 3:27:40 GMT
Hello Dr. Svalgaard, Once again thank you for making yourself available for questions. I have been busy for awhile now (seems like for ever) and have only been checking in here from time to time, so I hope my question is not a repeat... if it is, just slap me around and I'll go back to my cave. :-) Anyway, your post made me wonder exactly how tied together are the hemispheres of the sun. We have all been watching and waiting for cycle 24 to really get rolling, and most of the action is in the north. Furthermore, just using my mark one eyeball, the action in the north appears to have migrated closer to the equator then the southern hemisphere. Could the North be cycling faster then the south? How extreme can the differences become? They are often out of sync, see e.g. here: sidc.oma.be/html/wnosuf.htmlFor August SIDC reported the North produced 42.4 spots and the South 8.2 spots. That's a 5 fold disparity. That's a pretty heavy differential. |
|
|
|
Post by lsvalgaard on Sept 13, 2011 5:27:40 GMT
For August SIDC reported the North produced 42.4 spots and the South 8.2 spots. That's a 5 fold disparity. That's a pretty heavy differential. Significant, yes, but not unusual |
|
|
|
Post by Bob k6tr on Sept 15, 2011 2:05:59 GMT
Leif....Did you see that the SEM 304A Photon Count recorded today, 14-Sept, matched the high of Cycle 23 ?
|
|
|
|
Post by lsvalgaard on Sept 15, 2011 2:29:16 GMT
Leif....Did you see that the SEM 304A Photon Count recorded today, 14-Sept, matched the high of Cycle 23 ? No, I didn't, but one cannot conclude much from one day. |
|
|
|
Post by Bob k6tr on Sept 15, 2011 7:15:14 GMT
Leif....Did you see that the SEM 304A Photon Count recorded today, 14-Sept, matched the high of Cycle 23 ? No, I didn't, but one cannot conclude much from one day. No doubt But if this trend does hold up it might shed some light on the Blind Spot idea you postulated. When Cycle 23 Peaked the Daily Solar Flux readings were in the 260 - 270 Range and the Daily Sunspot number nearly broke 200. So if the reading is correct the Sunspot is down and the SFI is way down for the same level of UV Radiation. The problem is I'm not entirely sure of the reading. USC keeps changing the scale from a Quasilogrithmic to logrythmic and the historical charts are on a linear scale. Do you have any contact with Leonid Didkovsky ? |
|
|
|
Post by lsvalgaard on Sept 15, 2011 10:00:17 GMT
No, I didn't, but one cannot conclude much from one day. Do you have any contact with Leonid Didkovsky ? No. |
|
timb
New Member
Posts: 45 
|
Post by timb on Sept 15, 2011 22:47:11 GMT
For August SIDC reported the North produced 42.4 spots and the South 8.2 spots. That's a 5 fold disparity. That's a pretty heavy differential. Significant, yes, but not unusual With that much disparity, is there different N/S solar hemisphere rotational rates for the same latitude? Or another way to ask is one hemisphere slightly faster at the equator during this time and either creating a magnetic disparity or reacting to one? |
|
|
|
Post by lsvalgaard on Sept 16, 2011 5:20:35 GMT
Significant, yes, but not unusual With that much disparity, is there different N/S solar hemisphere rotational rates for the same latitude? Or another way to ask is one hemisphere slightly faster at the equator during this time and either creating a magnetic disparity or reacting to one? The hemispheres do often rotate at different speed, but that little to do with magnetic difference. The observed rotation is a surface phenomenon, while the magnetic field is generated at depth. |
|
timb
New Member
Posts: 45
|
Post by timb on Sept 16, 2011 17:52:36 GMT
With that much disparity, is there different N/S solar hemisphere rotational rates for the same latitude? Or another way to ask is one hemisphere slightly faster at the equator during this time and either creating a magnetic disparity or reacting to one? The hemispheres do often rotate at different speed, but that little to do with magnetic difference. The observed rotation is a surface phenomenon, while the magnetic field is generated at depth. Forgive me as I'm only hobbyist with this as I thought sunspots originated with plasma filaments on magnetic field lines and became complex/twisted due to rotation differences in the core vs. outerlayers. It also seems that if there were differences in surface velocity there might be a shearing component that disrupts/interacts with existing fields. For example, if the 31 degree latitude line had the same velocity in N and S hemipshere but the 30 degree latitude in N was faster than the 30 deg latitude in south, there would be more shearing force in the N and local surface dipoles would be stronger and that could account for N/S sunspot differences both in complexity and number. Is that even possible? If true, seems like interesting study to correlate L&P results (is the surface rotations becoming more uniform to account for lower gauss sunspots?). When sunspots in the N outnumber those in the S by large differences in number, are the sunspots also stronger in magnetic field? On Edit: a lot is answered here: solarcycle24com.proboards.com/index.cgi?action=display&board=general&thread=855&page=36 with the presentation. |
|
|
|
Post by Bob k6tr on Sept 24, 2011 21:06:46 GMT
When will be the next time that Bill Livingston scheduled for telescope time ?
|
|
|
|
Post by lsvalgaard on Sept 25, 2011 9:34:16 GMT
When will be the next time that Bill Livingston scheduled for telescope time ? He just had. I was with him. Give him a few days to reduce the data. |
|
|
|
Post by Bob k6tr on Sept 25, 2011 15:03:59 GMT
When will be the next time that Bill Livingston scheduled for telescope time ? He just had. I was with him. Give him a few days to reduce the data. There will be plenty of people consumed with anticipation over this one. This ought to be interesting ! |
|
|
|
Post by Bob k6tr on Oct 2, 2011 5:59:31 GMT
Leif are you awareof/follow what these guys are doing regarding this project of calculating "Effectivr Sunspot Number" ? www.nwra.com/spawx/ssne24.htmlIf so do you have any comments/observations ? |
|
|
|
Post by lsvalgaard on Oct 3, 2011 2:54:24 GMT
Leif are you awareof/follow what these guys are doing regarding this project of calculating "Effectivr Sunspot Number" ? www.nwra.com/spawx/ssne24.htmlIf so do you have any comments/observations ? yes, I am, but I have no particular comments. |
|
