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Solar Cycle 24 Begins
djellison
post Dec 30 2010, 12:17 AM
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I must be a mathematical dunce - how do you get an average of less than zero, when none of the sample values can ever be less than zero.
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nprev
post Dec 30 2010, 12:39 AM
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I'm not seeing it either. According to spaceweather.com, the spot number R formula is R=k (10g+s), where g is the number of sunspot groups, s is the number of spots, and k is a constant based on seeing conditions, "usually" <1.

I can see it being zero, but not less than zero. Suspect that the chart is messed up.

EDIT: Possible sorta-solution. Notice that one of the three curves (the dotted line) does not dip below zero. Suspect that this is probably the actual observation number, and the other two curves are statistical products of some sort whose math is not readily obvious.


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Hungry4info
post Dec 30 2010, 02:04 AM
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QUOTE (nprev @ Dec 29 2010, 06:39 PM) *
"usually" <1.

How much less? Only way R could be negative is if k < 0 (assuming physically meaningful values of g and s).

Edit: Found this. I don't know how much it applies since it doesn't seem to be a direct counting method.
QUOTE
Negative values are artifacts and are consistent with zero within the error limits.


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PDP8E
post Dec 30 2010, 04:03 PM
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I have a request in with the scientists that produced the graph.
When he/they gets back after the New Year, I should have the mathematical artifact that explains the negatives.


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djellison
post Dec 30 2010, 04:34 PM
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Where did it come from?
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PDP8E
post Dec 30 2010, 08:22 PM
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Doug,
The graph came from www.NWRA.com (Northwest Research Associates). They are first rate consultants, scientists, -etc.
http://www.nwra.com/spawx/ssne-cycle2324.html


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nprev
post Dec 31 2010, 03:10 AM
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My guess: They're using some sort of logarithmic expression in their calcs (any number below x exp 0 is gonna be negative.)


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djellison
post Dec 31 2010, 04:59 AM
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QUOTE (PDP8E @ Dec 30 2010, 12:22 PM) *
They are first rate consultants, scientists, -etc.


Oh - I don't doubt that whatsoever. I'm just scratching my head on the fact that all the observations go sub-zero.
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Gsnorgathon
post Dec 31 2010, 10:01 PM
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Note that none of the curves are observations - they're all calculated. So the mystery is just what is the calculation?

From their web page:

QUOTE
This plot provides a look at the progression of the NWRA effective smoothed sunspot number (SSNe) for solar cycle 23 and the start of cycle 24. The heavy solid curve is the smoothed SSNe (centered 13-month average), the light solid curve is the monthly average SSNe, and the dotted curve is a sunspot number calculated from the smoothed F10.7 solar flux. The foF2 and 10.7cm solar flux data used in these calculations were obtained from the NOAA SWPC.

Please note that the SSNe values plotted here were calculated in near real-time from a limited data set. If you are interested in post-analysis SSNe values calculated from a more representative data set, please contact NWRA.

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PDP8E
post Dec 31 2010, 11:06 PM
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Gsnorgathon is just about right.

Here is the email reply from NWRA:

....As indicated in the text on the referenced web page, the parameter in
question is an effective sunspot number, not an observed sunspot number.
It is more an index of the state of the ionosphere than of the sun,
although it does have a solar component. A negative value simply
indicates that the ionosphere is in a less-dense state than one would
expect for SSN=0. A more detailed explanation can be found in the link
"24hr SSNe" above the plot on the page you reference....



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PDP8E
post Jul 29 2011, 04:44 PM
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The Sun is still a little sleepy
NSO is calling for a drop in solar activity

The Maunder Minimum event is referenced twice...(!)

http://www.nso.edu/press/SolarActivityDrop.html

Here is a great video from Goddard about the last big Solar CME

http://www.youtube.com/watch?v=3czPxBfOFOg...player_embedded


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Guest_Sunspot_*
post Aug 9 2011, 09:49 AM
Post #27





Guests






By far the largest flare of the cycle so far - X7

From SDO
http://sdo.gsfc.nasa.gov/assets/img/browse...8_1024_0193.jpg
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Guest_Sunspot_*
post Sep 26 2011, 09:40 PM
Post #28





Guests






Very Strong geo magentic storm in progress, just saw the Aurora from Northern Cambridgeshire UK a few minutes ago.
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nprev
post Sep 26 2011, 11:34 PM
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Man...First time in a LONG time I'm sorry we don't live in Alaska anymore. Enjoy the show, you guys!!!!


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A few will take this knowledge and use this power of a dream realized as a force for change, an impetus for further discovery to make less ancient dreams real.
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Stu
post Sep 27 2011, 06:59 PM
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Missed the amazing aurora last night because the STUPID SKY ABOVE KENDAL WAS *&^%$ %^**&&^& %^***$ CLOUDY AGAIN!!!!!!!!

But, minor - very minor! - consolation, I got to take this photo of Jupiter shining above my castle...

Attached Image


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