Solar Cycle 24 Begins |
Solar Cycle 24 Begins |
Dec 30 2010, 12:17 AM
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#16
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Founder Group: Chairman Posts: 14448 Joined: 8-February 04 Member No.: 1 |
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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Dec 30 2010, 12:39 AM
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#17
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Merciless Robot Group: Admin Posts: 8789 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
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. -------------------- 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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Dec 30 2010, 02:04 AM
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#18
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Senior Member Group: Members Posts: 1453 Joined: 26-July 08 Member No.: 4270 |
"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.
-------------------- -- Hungry4info (Sirius_Alpha)
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Dec 30 2010, 04:03 PM
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#19
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Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
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. -------------------- CLA CLL
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Dec 30 2010, 04:34 PM
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#20
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Founder Group: Chairman Posts: 14448 Joined: 8-February 04 Member No.: 1 |
Where did it come from?
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Dec 30 2010, 08:22 PM
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#21
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Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
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 -------------------- CLA CLL
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Dec 31 2010, 03:10 AM
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#22
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Merciless Robot Group: Admin Posts: 8789 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
My guess: They're using some sort of logarithmic expression in their calcs (any number below x exp 0 is gonna be negative.)
-------------------- 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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Dec 31 2010, 04:59 AM
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#23
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Founder Group: Chairman Posts: 14448 Joined: 8-February 04 Member No.: 1 |
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Dec 31 2010, 10:01 PM
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#24
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Member Group: Members Posts: 259 Joined: 23-January 05 From: Seattle, WA Member No.: 156 |
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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Dec 31 2010, 11:06 PM
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#25
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Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
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.... -------------------- CLA CLL
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Jul 29 2011, 04:44 PM
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#26
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Member Group: Members Posts: 808 Joined: 10-October 06 From: Maynard Mass USA Member No.: 1241 |
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 -------------------- CLA CLL
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Guest_Sunspot_* |
Aug 9 2011, 09:49 AM
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#27
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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_* |
Sep 26 2011, 09:40 PM
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#28
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Guests |
Very Strong geo magentic storm in progress, just saw the Aurora from Northern Cambridgeshire UK a few minutes ago.
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Sep 26 2011, 11:34 PM
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#29
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Merciless Robot Group: Admin Posts: 8789 Joined: 8-December 05 From: Los Angeles Member No.: 602 |
Man...First time in a LONG time I'm sorry we don't live in Alaska anymore. Enjoy the show, you guys!!!!
-------------------- 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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Sep 27 2011, 06:59 PM
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#30
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The Poet Dude Group: Moderator Posts: 5551 Joined: 15-March 04 From: Kendal, Cumbria, UK Member No.: 60 |
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... -------------------- |
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