Sunspot 990, officially the 2nd sunspot of Cycle 24
April 14th, 2008 by Warwick HughesGo to solarcycle24.com and read about the latest member of the Cycle 24 family to appear.
For my other solar articles
In case the www.solarcycle24.com link changes:
Sunspot 990
04/14/2008 by VE3EN at 22:05The new sunspot has been numbered 990 by NOAA. This is now officially the 2nd sunspot of Solar Cycle 24. It is very small and poses no threat for solar flares. As you can see in the images below, the little speck is about all that makes up this region. It still maintains a nice SC24 magnetic signature.
In the latest STEREO Behind image below you can see SC24 Sunspot 990 and also what looks like a Cycle 23 region (old sunspot 987 perhaps) approaching the eastern limb.
Solar activity remains very low. The solar flux remains in the 60′s for now.
Posted in News and Views, Solar | 6 Comments »
April 16th, 2008 at 12:21 am
My spies tell me that Sunspot 990 has faded away. Many pages still to be written in this saga.
April 18th, 2008 at 10:56 pm
I blame global warming. Its causing the sunspots to melt.
solarscience.auditblogs.com/2008/04/19/solar-cycle-24-do-we-count-tiny-tims/
April 22nd, 2008 at 6:46 am
Ken Tapping on whether Solar Cycle 24 is really all that late
April 24th, 2008 at 9:24 pm
There were three recently published papers that predicted a solar magnetic cycle change to a Dalton or Maunder like minimum, for cycle 24: one analyzed past solar barycentre motion which correlates with deep solar magnetic cycle minimums, a second based on an analysis of the paleo cosmogenic isotopes (again that correlate with deep solar cycle minimums), and a third based on a physical model.
The following is the 2004 paper that predicts the sun is heading towards a Maunder minimum based on an analysis of the paleo record of solar activity.
adsabs.harvard.edu/abs/2004ApJ…605L..81B
This is the 2003 paper that predicts a solar cycle minimum based on a physical model.
adsabs.harvard.edu/abs/2003SPD….34.0603S
This is the 1987 Solar barycentre motion paper: Prolonged minima and the 179-yr cycle of the solar inertial motion by R.Fairbridge and J. Shirley
www.springerlink.com/content/w57236105034h657/
April 24th, 2008 at 9:40 pm
There are a number of paleoclimatic papers that note there is correlation with C14 and other cosmogenic isotopes changes and abrupt climatic change. For example Gerald Bond’s Persistent Solar Influence on North Atlantic Climate During the Holocene.
www.essc.psu.edu/essc_web/seminars/spring2006/Mar1/Bond%20et%20al%202001.pdf
“…The evidence comes from a close correlation between inferred changes in production rates of the cosmogenic nuclides carbon-14 and beryllium-10 and centennial to millennial time scale changes in proxies of drift ice measured in deep-sea sediment cores. A solar forcing mechanism therefore may underlie at least the Holocene segment of the North Atlantic’s 1500-year cycle…”
Another example is this paper which discusses the cause of the Younger Dryas abrupt climatic change which interrupted the current Holocene interglacial returning the planet back to the glacial phase.
“Reduced solar activity as a trigger for the start of the Younger Dryas?”
www.geo.vu.nl/~renh/pdf/Renssen-etal-QI-2000.pdf
From the paper:
“Estimates for the start of the YD all demonstrate a strong and rapid rise of C14 (Cosmogenic isotope that increases when there is decreased solar activity that hence allows increased galactic cosmic rays GCR to strike and interact with the atmosphere.) This change is the largest increase of atmospheric C14 known from the late glacial period and Holocene records.”
As to what is could be causing a semi periodic solar magnetic field change, a number of papers have been written concerning an observed correlation of solar inertial motion and the solar magnetic changes.
For example:
Prolonged minima and the 179-yr cycle of the solar inertial motion by R.Fairbridge and J. Shirley
www.springerlink.com/content/w57236105034h657/
This paper, “Can origin of the 2400-year cycle of solar activity be caused by solar inertial motion?” provides a full explanation of the solar mechanisms and a summary of previous papers concerning solar inertial motion and solar magnetic cycle changes.
www.ann-geophys.net/20/115/2002/angeo-20-115-2002.pdf
“..Time comparison of the epochs of high and low solar activity with climate alteration led to the conclusion that the cause of the approx. 2400-year cycle, both in the 14C concentration and in climate of the Earth, appears to be of a solar nature (Dergachev and Chistyakov, 1995)…”
“…The first basic cycle of solar inertial motion, the cycle of 178.7 years, was found by Jose (1965) in a repetition of solar motion characteristics computed between 1653 and
2060, and most important the time derivative of the Sun’s angular momentum was found…”
May 4th, 2008 at 8:20 pm
From Timo Niroma
Updated situation with sunspots.
The situation with sunspots from July 2007 to April 2008.
The cycle 23 that began already in 1996 still reigns superior. There was in March-April for 7 days 3 simultaneous spot groups from cycle 23 and 2 simultaneous groups for 5 days. One group from 23 lasted in January 11 days, and in February for 8 days, In March there were three separate 23 groups in 5.-17.3. and then the triplet began in 23., 24., and 25.3. The triplet decayed to doublet 1.4. and the last one was left alone 3.4. and decayed 4.4. In April there were still two separate groups in 19.-24.4. lasting together 5 days.
From cycle 24 there are two tiny signatures: one in January (1 day) and one in April (2 days).
So in 2008 there has been 10 groups from cycle 23 lasting together 68 days, and 2 groups from cycle 24 lasting together 3 days.
From July 2007 to December 2007
month
year
spotless days
days with below 10 Wolfs (1 sunspot group)
days with below 20 Wolfs (most probable 2 groups)
days between 20-30 Wolfs (3-4 groups)
07 2007 08 10 09 04
08 2007 08 22 01
09 2007 22 07 01
10 2007 28 02 01
11 2007 24 04 02
12 2007 12 05 05 08
——————————————————————-
January 2008
spotless days 20
one spot group from cycle 23 (southern hemisphere) on 11 days
one spot group from cycle 24 (northern hemisphere) on 1 day (4.1.)
4.1. there were two spot groups at the same time, one from cycle 23
and one from cycle 24
Sunspot number 3.4 (3.1 from cycle 23 0.3 from cycle 24)
——————————————————————-
February 2008
spotless days 21
one spot group from cycle 23 (southern hemisphere) on 8 days
none spots from cycle 24
Sunspot number 2.1 (all from cycle 23)
——————————————————————-
March 2008 (some ending in April)
spotless days 16
one sp-gr from cycle 23 (SH) on 2 days (5.-6.3.) max size 30 per mil
one sp-gr from cycle 23 (SH) on 1 day (10.3.) max size 90 pm
one sp-gr from cycle 23 (SH) on 3 days (15.-17.3.) max size 20 pm
a triplet (3 at the same time 25.3.-31.3.):
first sp-gr from cycle 23 (SH) on 12 days (23.3.-31.3.)
second sp-gr from cycle 23 (SH) on 13 days (24.3.-2.4.)
third sp-gr from cycle 23 (SH) on 13 days (25.3.-3.4.)
max size together 520 pm (26.3.), above 100 from 24.3.-2.4.
none spots from cycle 24
Sunspot number 9.3 (all from cycle 23)
——————————————————————–
April 2008
spotless days 20
remnants from sp-gr from cycle 23 1.4.-3.4. (see March)
one sp-gr from cycle 23 (SH) on 2 days (19.-20.4.) max size 20 pm
one sp-gr from cycle 23 (NH) on 3 days (22.-24.4.) max size 40 pm
one sp-gr from cycle 24 (NH) on 2 days (14.-15.4.) max size 10 pm
this is number 2 cycle 24 spot 102 days after the first in January
Sunspot number 2.9 (2.45 from cycle 23 and 0.45 from cycle 24)