2011-05-03

Minute-scale period oscillations of Earths magnetosphere Tied to The Sun's Coronal Mass Ejections

Vatic Note: As you have probably already guessed, I am a science nut, and enjoy it as a hobby. But let me make it clear, I am no expert in science so if anyone who is has anything to add to this, we would love to hear from you.   I suspect we have something here, because they are harassing me on this one.  I found that odd.  So maybe there is something here we are not suppose to know.   In order to avoid the disinfo, fear tactics of the khazars and their American puppets, its important to know and understand what is going on in your world. This is one of them. The powers that be are using HAARP to control all weather and are using science to scare us into all kinds of BS. One of which is that we are coming into an ice age..... right....so use haarp to make it warmer..... hahaha.......or the other one is the avoidance of talking about a magnetic and real pole shift and both at the same time.   These are important to know. 

Anyway, I thought you would like to really know what is going on with the sun and lumped this together with the blog showing the video displaying up close and personal, the activity on the sun which is horrific. The coronal ejections are massive like I had never seen before, but then I wasn't really looking. I am now,  as we all should be doing. Visit Soho and watch it live as it happens. Its a real education and don't forget about our blog on the new particles coming out from the sun that is mutating matter including neutralizing the Japanese radiation impact on us. You should reread that for some insight on the occult as well and their occult numbers that match numbers to do with the sun.... the basis originally of pagan religions was the sun in the beginning, of course they evolved both good and bad into whatever mans imagination was able to direct them, as we see today. Regardless, its an enjoyable journey of discovery when combined with the video we provided.

Minute-scale period oscillations of the magnetosphere
http://www.ann-geophys.net/29/663/2011/angeo-29-663-2011.pdf
S. Børve1,3, H. Sato2, H. L. P´ecseli2, and J. K. Trulsen1
1Institute of Theoretical Astrophysics, University of Oslo, Norway
2Department of Physics, University of Oslo, Norway
3Norwegian Defence Research Establishment (FFI), Norway
Received: 22 February 2011 – Revised: 14 March 2011 – Accepted: 25 March 2011 – Published: 13 April 2011

Abstract.
Oscillations with periods on the order of 5–10 min have been observed by instrumented spacecrafts in the Earth’s magnetosphere. These oscillations often follow sudden impacts related to coronal mass ejections. It is
demonstrated that a simple model is capable of explaining these oscillations and give a scaling law for their basic characteristics  in terms of the basic parameters of the problem.

The period of the oscillations and their anharmonic nature, in particular, are accounted for. The model has no free adjustable numerical parameters. The results agree well with observations. The analysis is supported by numerical simulations solving the Magneto-Hydro-Dynamic (MHD) equations in two spatial dimensions, where we let a solar wind interact with a magnetic dipole representing a magnetized Earth.

We consider two tilt-angles of the magnetic dipole axis. We find the formation of a magnetosheath with the
magnetopause at a distance corresponding well to the analytical results. Sudden pulses in the model solar wind sets the model magnetosphere into damped oscillatory motions and quantitatively good agreement with the analytical results is achieved.
Keywords. Magnetospheric physics (Magnetospheric configuration  and dynamics)

1 Introduction

The arrival of the pressure increase associated with the interplanetary shock driven by an interplanetary coronal mass ejection (ICME) will compress the low latitude geomagnetic field through an intensification of the Chapman-Ferraro magnetopause current. This leads to a sudden impulse (SI) which can be observed also in low latitude magnetometer records.
Correspondence to: H. L. P´ecseli
(hans.pecseli@fys.uio.no)

In a recent publication (Farrugia and Gratton, 2011) it was demonstrated that such SI-events are followed by large amplitude oscillations of 5 min periods. These are observed, for instance, by satellites in the cold, dense magnetosheath and in the hot and tenuous magnetosphere plasmas, consistent with other related observations (Plaschke et al., 2009).

It has also been found (Kivelson et al., 1984; Sibeck et al., 1989; Korotova and Sibeck, 1995) that magnetic pulsations with 8–10 min periods measured by geosynchronous satellites are well correlated with oscillations in the solar wind dynamic pressure.

It is the purpose of this communication to demonstrate that oscillations at these characteristic periods can be accounted for by a simple model of the magnetosphere. The entire problem of the coupling between the solar wind and the magnetosphere is extremely complicated even under quiet conditions, and will be even more involved during solar wind disturbances.

The main purpose of the present work is to reduce the analysis to its bare essentials, and then compare the results with observations and numerical simulations. The present approach is global, while some local models (Samson et al., 1992) study field line resonances associated with Magneto-Hydro-Dynamic (MHD) waveguide modes in the magnetosphere. Other models consider waves propagating in the equatorial plane between the flanks of the bow shock and a turning point deep within the magnetosphere (Harrold and Samson, 1992). Another approach considers the magnetopause surface analogous to an elastic membrane, obtaining its natural modes of oscillation (Freeman et al., 1995).

2 A simple model problem

Assume as a first approximation that the solar wind can be considered as a “wall” of ideally conducting material. Surface currents are induced in the solar wind, in such a way that  the Earth’s dipolar magnetic field together with the magnetic dipole is placed inside the solar wind, as indicated by the arrow to the left in Fig. 1a. We will not need this exact solution here, but be content with the overall variation. Note the two cusp points labeled Q on the figure, where the magnetic field intensity vanishes.

Using the mirror image and the basic expressions for a magnetic dipole, the construction of Fig. 1a is straight forward. For simplicity we let the magnetic dipole be parallel to the surface of the interface in Fig. 1a, this is a
trivial restriction.

The plane surface approximation is only locally valid: the surface containing the current paths is distorted as illustrated  in Fig. 1c). The topology of the surface currents is however not changed. The plane surface model can therefore be used as an approximation as the tangent plane at the stagnation point (or “nose region”) of the solar wind. The model assumes an ideally conducting solar wind.

(Click on link above to read remainder of the article.)

The article is reproduced in accordance with Section 107 of title 17 of the Copyright Law of the United States relating to fair-use and is for the purposes of criticism, comment, news reporting, teaching, scholarship, and research.

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