Syntheses, Creativity and Paradigm Change

In this short paper, I emphasized that creativity in research is best demonstrated by a synthesis effort of observed facts, which could bring a paradigm change and produce a step-wise progress (“breakthrough”) in science

Need for Morphological Study in Natural Sciences

The importance of morphological study is emphasized in natural sciences. In morphological studies, one synthesizes all the available observed facts, sequencing them in terms of causes and effects under a specific principle. It can provide not only an opportunity of breakthrough, but also the foundation of a significant theoretical research. It is the stage where creativity and innovativeness can most clearly be displayed

The Explosive Characteristics of the Aurora: The Electric Current Line Approach

The aurora shows explosive activities a few times in 24 h on a moderately active day. This specific phenomenon is called the auroral substorm, which consists of the growth, expansion, and recovery phases; the explosive activities occur during the expansion phase. As an introduction, the explosive activities of the aurora are morphologically described on the basis of ground-based all-sky and satellite images. In terms of theoretical understanding, the processes for the explosive activities have been considered almost exclusively in terms of “the magnetic field line approach” in the past, including the process of magnetic reconnection. Instead, in this paper, we consider the substorm processes in terms of “the electric current line approach.” This approach requires that the whole process of auroral substorms should be considered as a chain of processes, which consists of power supply (dynamo), transmission (currents/circuits), and dissipation (auroral substorms). An increased power of the solar wind-magnetosphere dynamo intensifies (to the level of 1011w = 5 × 1018 erg/s), the electric current mainly in the main body (just outside of the ring current) of the magnetosphere increases, resulting in accumulating energy in its inductive circuit (≈6 Re), and inflation of the magnetosphere. When the accumulated energy reaches about 5 × 1015 J (= 5 × 1022 ergs), the magnetosphere tends to become unstable (because of current instabilities). As the current intensity is reduced as a result, the magnetosphere is deflated. It is suggested that it is in this deflation process, during which the accumulated energy is unloaded, and an earthward electric field (5–50 mV/m) is produced on the equatorial plane, establishing the unloading current system (the UL current system), which is responsible for the unloading expansion phase, including the most characteristic features of the expansion phase, such as the poleward advance of the aurora and the development of the auroral electrojet. The electric current approach is rather new and needs much more effort to develop

A study of magnetic storms and auroras

New notations for magnetic disturbance fields are proposed, based on the theoretical consideration of the electric current systems by which they are produced. A typical magnetic storm begins suddenly when the onrush of the front of the solar gas is halted by the earth's magnetic field. This effect (DCF field) is most markedly observed as a sudden increase of the horizontal component of the earth's field (the storm sudden commencement, abbreviated to ssc)— like a step function. In many cases, however, the change of the field during the ssc is more complicated, and different at different places. Such a complexity superposed on the simple increase (DCF) is ascribed to a complicated current system generated in the polar ionosphere (DP current). It is found that the changes of electromagnetic conditions in the polar regions are communicated, without delay, to lower latitudes, even down to the equatorial regions. It is inferred that the equatorial jet is affected by such a change and produces the abnormal enhancement of ssc along the magnetic dip equator. From the extensive analysis of several magnetic storms that occurred during the IGY and IGC, it is suggested that the capture of the solar particles in the outer geomagnetic field occurs when irregularities (containing tangled magnetic fields and high energy protons) embedded in the solar stream, impinge on the earth.. Thus the development of a magnetic storm depends on the distribution of such irregularities in the stream. The motions and resulting currents and magnetic fields of such "trapped" solar particles are studied in detail for a special model. It is inferred that a large decrease (DR field) must follow the initial increase; it is ascribed to the ring current produced by such motion of solar protons oi energy of order 500 Kev. It is proposed that during the storm there appears a transient 'storm-time1 belt well outside the outer radiation belt. It is predicted that the earth's magnetic field is reversed in limited regions when the ring current is appreciably enhanced. This involves the formation of neutral lines there. These may be of two kinds, called X lines or 0 lines according as they are crossed or encircled by magnetic lines of force. These may be entirely separated or may be joined to form a loop, called an OX loop. It is shown that one of them, the X line, which is connected with the auroral ionosphere by the lines of force, could be the proximate source of th<e particles that produce the aurora polaris. By postulating the existence of such X-type neutral lines at about 6 earth radii, an explanation is obtained of the detailed morphology of the aurora. This includes the auroral zones and their changes, the nighttime peak occurrence of auroras, their thin ribbon-like structure and their multiplicity, their diffuse and active forms and the transition between them (break-up) the required electron and proton flux, and the ray and wavy structures. Among the most important phenomena associated with the sudden change of the aurora from the diffuse to the active form are the simultaneous appearance of the auroral electrojet and the resulting polar magnetic disturbances (DP sub-storms). Several typical DP sub-storms are studied in detail. It is concluded that a westward auroral jet is produced by a southward electric field. It is shown that an instability of the sheetbeam issuing from along the X-type neutral line can produce a southward electric field of the required intensity. The southward electric field produces an eastward motion of the electrons in the ionosphere. This may be identified with the eastward motion of an active aurora and with the westward auroral electrojet. Besides such large changes- of the field, there often appear various quasi-sinusoidal changes of the field, much less intense. They are supposed to be hydromagnetic waves, some of which are generated in the outer atmosphere and propagated through the ionosphere, where a certain amount of their energy is dissipated. It is concluded however that Such a dissipation is not sufficient to produce any appreciable heating of the ionosphere.Chapter I The electromagnetic environment of the earth : The solar system in the Galaxy ; The sun and the interplanetary space ; The outer atmosphere, the Van Allen radiation belts and the ionosphere ; The earth’s permanent magnetic field ; Introduction to geomagnetic storms and auroras ; The analysis of the earth’s magnetic field – Chapter II The sudden commencement of magnetic storms : Introduction ; The studies of Sc and Si at individual observations ; A theory of the Sc of magnetic storms ; Transmission of the Sc from the inner boundary of the solar steam to the earth’s surface ; The sudden commencement DP currents – Chapter III The ring current and the van allen radiation belts : Introduction ; The motion of charged particles in the earth’s dipole magnetic field ; Electric currents in an ionized gas (general formulae) ; The steady ring current in a dipole field ; The magnetic field produced by the ring current ; The main phase of magnetic storms ; The ring current belt ; Discussion – Chapter IV A neural line discharge theory of the aurora Polaris : Introduction ; The formation of a neutral line ; The motions of charged particles close to a neutral line ; The auroral zones ; Particle injection associated with arcs ; Rayed arcs ; Instabilities of auroras – Chapter V Polar magnetic disturbances : Introduction ; The polar magnetic disturbances of 5 to 6 December 1958 (College, Alaska) ; The polar magnetic disturbances of 29 September 1957 (Worldwide) ; The polar magnetic disturbances of 23 September 1957 ; The eastward motion of auroras and the electric field of polar magnetic disturbances ; The origin of the electric field of polarmagnetic disturbances – Chapter VI Hydromagnetic waves in the ionosphere : Introduction ; Ionospheric heating by hydromagnetic waves connected with geomagnetic micropulsations – Acknowledgements -- ReferencesYe

The basic solar wind speed distribution and its sunspot cycle variations

In this paper, it is suggested that the latitudinal solar wind speed observed by the Ulysses spacecraft during the lowest solar activity (when both the ecliptic and magnetic equators coincide) may be identified as the basic speed distribution throughout the solar cycle. We demonstrate this suggestion by rotating this particular Ulysses distribution counterclockwise up to 70° in accordance with the rotation of the equivalent dipole axis during active periods of the cycle. The corresponding magnetic equator in the Carrington map latitude-longitude (27 days) becomes quasi-sinusoidal with respect to the ecliptic equator. The quasi-sinusoidal magnetic equator on the Carrington map and its modification associated with the degree of sunspot activities can explain the two high speed peaks (750–800 km/s) and the two lowest speed (350 km/s) during 27-day solar rotation periods, most clearly recognizable after the sunspot peak period. Thus, it may be not necessary to consider coronal holes or open regions as the source of high speed streams. In fact, this particular (lowest solar activity) Ulysses distribution may represent the speed distribution pattern by the basic generation process of the solar wind itself

チジキ アラシ ト ソノ タイヨウゲン タイヨウ カツドウ ジョウショウキ

太陽は地球よりも千倍以上速く磁極を反転する磁変星なので,大規模現象を記述するために,緯度にhelioGRAPHIC,経度にhelioMAGNETIC という折衷型座標系を適用した.地磁気嵐はその発生の周期性から,突発性と回帰性の二種に大別される.突発性地磁気嵐の原因とされる太陽フレアは,この座標系でNE四半球とSW 四半球に分布し,回帰性磁気嵐の太陽源であるコロナホールは,経度0°と180°線に沿って分布することが明らかになり,この太陽サイクルに依存しない不変則はNEWS の法則と名付けられた.この法則は,流源面中性線がsingle wave として現れる太陽活動下降期に顕著であるが,上昇期にしばしば現れるdouble wave を二つのsingle wave に分けると,それぞれについて下降期と全く同様にNEWS の法則が成立することが明らかとなり,少なくとも上昇・下降期には太陽活動phase にも依存しない不変則であることが明らかになった.Solar phenomena, including solar flares and coronal holes, are considered in the context of a NEWS coordinate system, obtained by application of the heliographic and heliomagnetic coordinate systems to the solar latitude and longitude, respectively. By expressing the occurrence of solar phenomena in terms of NEWS coordinates, we discovered that solar flares tend to converge in the NE and SW quadrants of the solar disk, where they act as sources of sporadic storms. Meanwhile, coronal holes converge to solar longitudes of 0° and 180°, where they are sources of recurrent storms. Because of their concentration in the NE- and SW-quadrants, this correlation is referred to as the \u27NEWS law\u27. The neutral line of the source surface shows a beautiful single wave in its declining phase, while it tends to show a double wave in the rising phase. Solar rotation numbers 2118 to 2119, where the neutral line exhibited two complicated asymmetric waves in both the N-S and S-W directions, were chosen for detailed analysis. Notwithstanding such an extremely complicated case, the NEWS law is satisfied when the double wave is separated into its two single-wave parts

Space Plasma Physics: A Review

Owing to the ever-present solar wind, our vast solar system is full of plasmas. The turbulent solar wind, together with sporadic solar eruptions, introduces various space plasma processes and phenomena in the solar atmosphere all the way to Earth’s ionosphere and atmosphere and outward to interact with the interstellar media to form the heliopause and termination shock. Remarkable progress has been made in space plasma physics in the last 65 years, mainly due to sophisticated in situ measurements of plasmas, plasma waves, neutral particles, energetic particles, and dust via space-borne satellite instrumentation. Additionally, high-technology ground-based instrumentation has led to new and greater knowledge of solar and auroral features. As a result, a new branch of space physics, i.e., space weather, has emerged since many of the space physics processes have a direct or indirect influence on humankind