A Possible Reason for the 1.3 year Solar Oscillations near the Sun's Tachocline

Back in 2006, I was investigating the possibility that variations 

in planetary gravitational/tidal forces might be linked with the 

newly discovered 1.3 year oscillations seen near the Sun's

Tachocline boundary.

Howe et al. Science 31 March 2000: Vol. 287 no. 5462 pp. 2456-2460  

Dynamic Variations at the Base of the Solar Convection Zone


ABSTRACT 

We have detected changes in the rotation of the sun near the base 

of its convective envelope, including a prominent variation with a 

period of 1.3 years at low latitudes. Such helioseismic probing of

 the deep solar interior has been enabled by nearly continuous 

observation of its oscillation modes with two complementary 

experiments. Inversion of the global-mode frequency splittings 

reveals that the largest temporal changes in the angular velocity 

Ω are of the order of 6 nanohertz and occur above and below the

 tachocline that separates the sun's differentially rotating convection 

zone (outer 30% by radius) from the nearly uniformly rotating deeper 

radiative interior beneath. Such changes are most pronounced near 

the equator and at high latitudes and are a substantial fraction of the

 average 30-nanohertz difference in Ω with radius across the 

tachocline at the equator. The results indicate variations of rotation 

close to the presumed site of the solar dynamo, which may generate 

the 22-year cycles of magnetic activity.

The plot below shows a Fast Fourier Transform (FFT) Spectra 
of the Solar Motion about the Barycentre of the Solar System 
caused by the Terrestrial planets.

 The Solar Baycentric motion due to the Terrestrial planets is 

dominated by the Synodic periods of Venus/Earth (= 1.5593 yrs)

and Earth/Mars (=2.13 years). Also evident in this plot is the 

~ 6.4 year beat period between these two synodic periods

(i.e. Venus/Earth and Earth/Mars).

Now, I knew that Jovian planets act like a large washing 

machine, stirring the inner terrestrial planets with a 

gravitational force that varies with a frequency that is 

determined by the beat period between two main competing 

Jovian planetary alignments.

The first is that produced by the the retrograde tri-synodic 

period of Jupiter/Saturn ( = 59.577 yrs) and the second is 

the pro-grade synodic period of Uranus/Neptune (171.41 yrs):

(59.577 x 171.41) / (171.41 + 59.577) = 44.21 yrs

This driving period of the Jovian planets closley matched 

the synodic periods of the three largest Terrestrial planets 

with Jupiter: 

69 × SVJ = 44.770 yrs    SVJ = synodic period Venus/Jupiter

41 × SEJ = 44.774 yrs    SEJ = synodic period Earth/Jupiter

20 × SMJ = 44.704 yrs    SMJ = synodic period Mars/Jupiter

The 44. 7 year period for the three largest Terrestrial planets 

to realign with Jupiter appears to link Jupiter's orbital period 

directly into the time it takes for the three largest terrestrial 

planets to return to their same (relative) orbital configuration, 

which just happens to be 6.40 years:

4 x SVE = 6.3946 yrs  SVE = synodic period Venus/Earth

3 x SEM = 6.4059 yrs SEM = synodic period Earth/Mars

7 x SVM = 6.3995 yrs SVM = synodic period Venus/Mars

28 × SVE = 7 x (6.3946 yrs) = 44.763 yrs   

This lead me to propose that resonances in the relative 

motion of the Jovian planets had effectively molded and 

shaped the orbital periods of the three main terrestrial 

planets, producing the 6.4 year period for their orbital 

realignment. 

In addition, I proposed that the gravitational/tidal pumping 

action of the Jovian planets would lead to a 6.4 amplitude 

modulation of the dominant 1.6 year frequency of the Sun's 

Barycentric motion [See the graph above], producing two 

side-lobes, one at 1.28 years and the other at 2.13 years. 

I speculated that it was this ~ 1.3 year side lobe that was 
driving the fundamental solar oscillation that Howe et al. 
2000 had observed near the Tachocline boundary. 


This "discovery" lead me to think that the relative orbital
configurations of the Jovian planets were not directly 
responsible for modulating/driving the level of solar activity 
on the Sun. Instead, I began to realize that it was more likely 
that the motion of the Jovian planets had molded the orbital
periods of the terrestrial planets and it was the tidal effects
of the latter (i.e. mostly due to tidal alignments of Venus
and the Earth) that were directly responsible for 
driving/modulating the Sun's activity, especially when they 
were coupled with the effects of Jupiter's dominant 
gravitational force acting upon the convective layers of the
Sun.


This revelation lead me to propose the tidal-torquing
(spin-orbit coupling) model that I have outlined at: 


http://astroclimateconnection.blogspot.com.au/2012/03/planetary-spin-orbit-coupling-model-for.html