Wednesday, November 18, 2009

Sunspot Cycle Late - Is it the Planets?

The sunspot cycle averages 11.1 years. But it is variable. It can be late or early and vary in length by a couple years. Solar physics has come a long way in the last several decades but predictions when the minima and maxima should occur is still fraught with uncertainly.

Currently (late 2009) Astronomers are been perplexed with the next sunspot cycle (number 24). While the first sunspot belonging to cycle 24 appeared in January 2008 the rate should have been recovering with a peak expected in 2011. Yet sunspots have been absent for weeks at a time for more than a year and now it looks like the peak is expected in 2013-about 2 years late.

In a now out-of-print tome called Recent Advances in Astrology (Analogic 1977), Geoffrey Dean and Arthur Mather demonstrated a correlation between the 11-year sunspot cycle with the cycles of the planets. The book is a review of astrological research (mostly negative) up to 1976 but includes section on geocosmic research too. Their thesis suggested some kind of planetary resonance was regulating the peaks and troughs of the sunspot cycle. As the planets orbit around the Sun they periodically make specific geometric angles with one another as seen from the Sun. In astrological lore they are called aspects.

They found Pluto and Neptune have been moving in an out of a 60° aspect for several decades. Whenever they arrive at 60° apart the sunspot maximum envelope tends to be exceptionally high - as if these two planets were "pulling" the envelope upward from normal.

In addition the midpoint (the bisection of the angle) between Jupiter and Neptune aligns at 90° (right -angles) to the solar equator with almost every cycle minimum.

Thus these two planetary cycles combine to regulate the extent of solar maxima, the timing and synchronization of solar minima respectively.

Now this could of course be all just coincidence. There are after all dozens of different planetary combinations that can fortuitously match up with the solar cycle. In fact Dean and Mather list about 30 of them in their book to be sure. However the clustering of planetary cycles of around 22.2 years is remarkable which lends some credence to the idea. The 22.2 year cycle is the full cycle when the magnetic polarity of the sunspots flip from north to south every 11.1 years. When the first spot from cycle 24 appeared its polarity was opposite from those of cycle 23. That's how we knew cycle 24 kicked in.

The Pluto-60°-Neptune and Jupiter/Neptune-90°-Solar equator was particularly eye-catching in a graphic illustration on page 513. I have recreated the graph with updated data below. Their their graph ends at 1977 with projection into the 80's. My graph continues the projection through to 2030.

Click on image to enlarge

Neptune - Pluto aspects
The above graph shows the monthly smoothed sunspot cycle since 1750. The orange line is the envelope over the period. High maxima are seen when there are multiples of 60° occurring. This is when Neptune and Pluto are 60°, 120° and in some cases 30° apart. By contrast the maxima tend to be suppressed when Neptune and Pluto are 0° and 90° apart.

Jupiter/Neptune midpoint on solar equator
Light blue arrows indicate sunspot minima. Magenta arrow shows the Jupiter/Neptune cycle coinciding with most minima. Note how the minimum of cycle 2 begins synchronized then runs out of synchronization and snaps back at cycle 6. Synchronization are marked with green arrows. The minima drift ahead and behind the planetary cue every 4 to 5 cycles.

One wonders - past behaviour is often a good predictor of future behaviour. The lateness of upcoming cycle 24 is 5 cycles behind the last synchronization at cycle 18, so we appear to be due for another resynchronization event with upcoming cycle 24. Jupiter/Neptune-90°-solar equator is due for February 2010. It appears the minimum of the current cycle 23 is dragging itself out so as to rendezvous up with Jupiter/Neptune on time!

As for the overall envelope it appears cycle 24 will be moderate strength, neither strong nor weak as it leads up to cycle 25 that aligns for the last time time with Neptune-60-Pluto series. This suggests that cycle 25 maximum about 2029 could be as large as cycle 19 in 1957. However see this. There are no more 60° or 120° Neptune-Pluto aspects due for decades.

How planets could possibly affect or regulate solar cycles is difficult to model as the gravitational effects are minuscule. Dean and Mather however do suggest that gravitational resonance is a possibility. It works like this. Any system that is finely tuned to a frequency generator (planet to Sun) can respond to minuscule resonant forces triggering potential energy at the point of release such as magnetic fields in the Sun. Radio engineers working with communications are familiar with this as a matter of course. For example, tuned TV and radio receivers generate obvious images and sound by virtue of very faint, milliwatt radio frequency signals collected by an antenna then amplified by the receiver power input.

Does it Explain The Maunder Minimum?

Between about 1650 and 1700 sunspots were almost absent. This is known as the Maunder Minimum. It coincided with the so-called Little Ice Age when temperatures in Europe were below average during the period. Do the planets have something to say about this period?

Click on image to enlarge

During the Maunder Minimum Pluto and Neptune were approximately between 150° and 180° apart - or in astrological terminology, in opposition. It was as if a planetary hand was placed down suppressing sunspot activity eliminating maxima and minima for the period!

The maxima resumed gradually when Neptune and Pluto formed into a 120° aspect. Note again in the time-line that follows how subsequent 120° and 60° increase the maxima envelope and 0° and 90° suppress maxima envelope.

So we therefore have two specific classes off angular relationships between Neptune and Jupiter that define the magnitude of maxima. Those the divide the the circle by 3 and 6 into 120° and 60° (known as the 3rd and 6th harmonic) coincide with increase in maxima. Those that divide the circle by 2 and 4 into 180° and 90° (known as the 2nd and 4th harmonic) coincide with suppressed maxima.