Some years ago I tried to solve the mystery of the solar cycle, and now I had another look with fresh eyes and discovered some interesting new aspects.

My approach is intuitive, observing that the solar cycle is of lenght similar to the Jupiter period of 11,86 years and half of the Jupiter-Saturn synodic period of 19,86 years.

If planets can influence the solar cycle, it would be natural to look at the two largest planets that should have a dominating effect. Gravtitional effects have been proposed earlier, and the fenomenon of superflares hints to interaction between electromagnetic fields. Whatever the interaction-mechanism may be, what are the cycles telling us?

This will be a shortened presentation, leaving out many useful and interesting interpretations and conclusions that I probably will present later.

1- Position of Jupiter at Solar Minimum

Using the software Asynx Planetarium I found the angular position of Jupiter at each solar minimum. Here is the plot versus the sunspot number of the cycle after the minimum (Fig1)

Solar minimum seem to cluster around two intervals of Jupiter-angle, around 54 and 311 degrees. The Jupiter perihelion is at ~14 deg.

I will name the group at 54 deg (A) and at 311/-49 deg will be (B). Those in between will be (C).

Then I move the scale 180 deg, and divide into two plots of cycle 1-17 and 18-23 (Fig2)

Observation:

-Solar cycle minimum get caught in group A and the length of the next cycles are "forced" to be similar to the Jupiter period.

-After some cycles a shorter cycle is produced, moving the next minimum to group B

-Then the minima are forced to stay in group B, again producing long cycles similar to the Jupiter period

-After some cycles a shorter cycle is produced, moving the next minimum into group C

-In group C the cycles are shorter, and move towards group A where they are caught again

-There is one deviating cycle SC4 that makes a move in the opposite direction B to A

Looking at some caracteristics for the groups:

-cycles of very low sunspot number are found in group A and B

-Average strength: A 119 - B 112 - C 110

-Average length: A 10,8 - B 11,6 - C 10,2

-Cycles in group B need less time to reach their maximum, relative to their cycle length

This is how the timeline looks like (Fig3)

-SC3-15 were caught by A&B (13 cycles) before moving through group C

-SC4 an anomaly

-SC 19-23 (5 cycles) so far caught by group A&B

-are we experiencing a short period in A&B and soon going into C, or will we stay in B for several cycles ahead?

There is some factor missing here... it´s the Jupiter-Saturn connection:

2-The relative Jupiter-Saturn angle at minimum

Plotting the relative Jupiter-Saturn angle at solar minimum (Fig4)

Observations:

-Solar minimum cluster around JuSa-angles of 70 and 250 degrees

-Distinct intervals that determine the next cycles strengt and length

-Some overlapping intervals where the resulting cycle can fall in either class. The special cycles that are short and weak, or long and strong often happen here.

-An estimate for SC24 is plottet, assuming it will begin sometime in 2009. Estimate SSN ~75 and length ~12 years

Here another way to illustrate the JuSa-angle vs strength, where the scale is doubled and every point is plotted twice (Fig5)

The JuSa-angle at minimum also gives a good hint about the time from minimum to maximum of the next cycle (Fig6)

Here is how the minima jump between the two favorable angle-intervals, and sometimes gets out of synch to produce long and weak cycles (Fig7)

Now it could be interesting to see whether the Jupiter-angle at minimum (A, B or C) has any interaction with the Jupiter-Saturn angle (Fig8)

Observation:

-at low angles the B cycles are stronger than A, and at high angle the A cycles are stronger than B

3-Temporary conclusion

The Jupiter angle seem to play an important role to where/when the solar minimum happen (or at what time the next cycles begins)

The Jupiter-Saturn angle seem to be important in determining the next cycles length and strength

There are two favorable Jupiter-angle intervals where minima happen. Jupiter tries to force the cycle to stay in these intervals, forcing the cycle up over 11 years. As the cycles stay in these intervals A&B, very weak cycles can occur.

There are two favorable Jupiter-Saturn-angle intervals where minima tend to happen. Jupiter-Saturn tries to force the cycles down towards ~10 years to stay within these intervals. When a cycle falls out of sync, it stays out of sync for several cycles and produce very weak and long cycles.

4-Speculation - looking back before 1750

5-Speculation - what will the future bring? A forecast

6-The Tug of War of Solar Cycle Length: Ju vs JuSa (in progress)

coming:

7-Looking on accumulated cycle length and tidal peaks

8-Looking closer at the Jupiter connection - what does it mean?

9-Looking closer at the Jupiter-Saturn connection - what does it mean?

10-Looking at Ju-solar cycles

11-Looking at JuSa-solar cycles

12-Synodic periods Sa-Ur (45,36 yr) and Ur-Ne (171 yr)

Dec.25, 2008

Jan Benestad

Trondheim, Norway

jan.benestad@broadpark.no

www.sibet.no