鄱阳湖洪水灾害与太阳活动周期相关性研究

鄱阳湖是洪水灾害频发地区,1755年至2008年,共计23个太阳活动周的254年内,鄱阳湖发生洪水年份101次,发生洪水的比率为39.76%,平均每个太阳活动周期内发生洪水4.39次.鄱阳湖发生洪水的频次与太阳活动磁周期无关.太阳活动极期发生鄱阳湖洪水的概率较高,在太阳活动极大期和极小期发生洪水的概率分别为47.82%和60.86%,在同一太阳活动周期内极大期和极小期同时发生洪水的概率较小.一般情况下不会出现连续三个极期都发生洪水的现象,若不考虑太阳活动极期的洪水发生次数,太阳活动周下降期发生洪水的概率最小.     

关于二十一太阳周期上升阶段中太阳活动的评述

本文阐述了在二十一太阳周期上升相期间太阳黑子、钙谱斑、2800MHz射电流量和太阳耀斑、质子耀斑、质子事件的活动情况。我们的统计结果表明,在这个时段,太阳活动通过三次脉冲性上升达到极大。 本文确定了上升相的活动经度:L160°～210°和L50°～90°。并对最强的活动区进行了讨论。     

太阳活动对中国中纬度地区8级大地震的可能触发

研究了发生在中国中纬地区(20°~40)°Ms≥8的大地震与太阳活动的关系,发现地震的发生时间多处在太阳活动周的降段至谷段,并且具有统计意义,显示出太阳活动和地震活动的相关联性。联想到中纬度地区洪水与太阳活动负相关,即在太阳活动低年,降雨充沛,甚至发生水灾。作者认为大雨引起的地下水位上升,岩石被水浸泡后,耐剪强度下降,从而使已孕育的大地震容易触发。     

质子耀斑的日面分布特征

在２２太阳活动周中，日面上有三个较强的质子活动复活体，它们爆发峰值流量≥１００ｐｆｕ和≥１０００ｐｆｕ的质子耀斑各占同类耀斑总数的７０．４％和８３．３％。活动复活体分别位于北纬２６°─３５°和南纬２０°─２９°纬度带上，由于它们周期性（１─２．６年）地再现，从而形成了日面质子耀斑的活动经度和纬度明显集中趋势。     

分析昆明GPS站相对欧亚板块的运动

利用国际联测和综合处理 ,得到昆明GPS站地壳形变速率每年以( -4 .3± 0 .5)mm下沉趋势 ,水平分别以 3 7.5mm ,方位 1 47°± 1 .°5运动。利用最新国际地球自转服务 (IERS)发布的国际地球参考架ITRF2 0 0 0速度场 ,建立最新反映全球板块模型 ,基于最新的ITRF2 0 0 0地球参考架和欧亚板块的欧拉矢量 ,估计得到昆明站的地壳垂直形变速率为每年 -0 .0 1mm呈下降趋势 ,水平形变速率为每年 ( 8.1± 0 .2 0 )mm ,方位 1 3 7°± 1 .°5;并进一步分别基于几百万年地质地磁模型NNR -NUVEL1A和ITRF96、ITRF97模型的欧亚板块的欧拉矢量 ,得到较一致的结果 ,说明全球板块运动稳定性与模型的可靠性。本文基于不同板块模型分析了昆明GPS站相对于欧亚板块运动     

第22太阳周首次大质子事件的预测

本文通过对过去质子事件的分析,发现首次大质子事件都发生在每个太阳活动周开始后1.9年,从而得到第22太阳周首次大质子事件可能发生时段的预测。     

天象观测 2001年1月天象 2001年2月天象

月初 ,太阳的视赤纬为 -2 3°0 5′ 4 ;月末 ,太阳的视赤纬为 -1 7°2 5′ 3。本月太阳由人马座运行至摩羯座。5日 1 4时 4 9分小寒 ,太阳的黄经为 2 85°。2 0日 8时 1 6分大寒 ,太阳的黄经为 30 0°。月亮过近地点、远地点的时间分别为 1 0日 1 7时、2 5日 3时。月相为上弦、望、下弦、朔的时间分别为 3日 7时、1 0日 4时、1 6日 2 1时、2 4日 2 1时。1 0日 4时将发生月全食 ,我国不可见。水星由人马座经摩羯座运行至宝瓶座。 1 4日 1时水星合海王星 ,水星位于海王星南面 2°。 2 3日 1时水星合天王星 ,水星位于天王星南面 0° 4。 2 6日1…     

21世纪云南第1次大震活跃期的趋势预测

在太阳活动与地震活动相关研究的基础上指出：在周期性太阳活动的调控下，地震活动也显示出与太阳活动相关的周期性变化。云南22年的地震周期在20世纪形成了4个大震活跃期和4个相对平静期。根据地震活动和太阳活动的若干相关规律，对云南地区在本世纪第1次大震活跃期的到来作了趋势性预测：云南在本世纪第1次大震活跃期的第1个大震(M=7．0左右)将于2012年到来，那时正是太阳活动第24周下降段的开始，离上次大震活跃期的最后一个大震(丽江，M=7．0，1996年)恰好是16年。在该大震活跃期里，还将发生若干个M=7．0左右的大震和一些较小的地震，其大震爆发的时间将遵循Tx=(Tn—Tn—1)^1/2(a年)的非线性经验规律发生。     

天象观测

二○○二年三月天象 月初,太阳的视赤纬为-7°44′2;月末,太阳的视赤纬为+4°00′0。本月太阳由宝瓶座运行至双鱼座。 6日2时27分惊蛰,太阳的黄经为345°。 21日3时16分春分,太阳的黄经为0°。     

1959年7月10日太阳特大耀斑的H_α光谱分析

1959年7月10日在太阳日面經度λ=327.5°日面緯度φ=18°处爆发了一个特級大耀斑,这个耀斑从发生起到消失几乎延續了四个小时之多,我們对这个大耀斑作了光譜的观測,本文就是介紹对在耀斑极強期間获得的光譜資料所作的分析,分析的目的在于通过理論輪廓的比較确定在耀斑中可能存在的物理状态。     

On the origin of the solar system and the exceptional position of the Sun in the Galaxy

The solar system's position in the Galaxy is an exclusive one, since the Sun is close to the corotation circle, which is the place where the angular velocity of the galactic differential rotation is equal to that of density waves displaying as spiral arms. Each galaxy contains only one corotation circle; therefore, it is an exceptional place. In the Galaxy, the deviation of the Sun from the corotation is very small — it is equal to ΔR/R _⊙≈0.03, where ΔR=R _c ?R _⊙,R _c is the corotation distance from the galactic center andR _⊙ is the Sun's distance from the galactic center. The special conditions of the Sun's position in the Galaxy explain the origin of the fundamental cosmogony timescalesT ₁≈4.6×10⁹ yr,T ₂?10⁸ yr,T ₃?10⁶ yr detected by the radioactive decay of various nuclides. The timescaleT ₁ (the solar system's ‘lifetime’) is the protosolar cloud lifetime in a space between the galactic spiral arms. The timescaleT ₂ is the presolar cloud lifetime in a spiral arm.T ₃ is a timescale of hydrodynamical processes of a cloud-wave interaction. The possibility of the natural explanation of the cosmogony timescales by the unified process (on condition that the Sun is near the state of corotation) can become an argument in favour of the fact that the nearness to the corotation is necessary for the formation of systems similar to the Solar system. If the special position of the Sun is not incidental, then the corotation circles of our Galaxy, as well as those of other galaxies, are just regions where situations similar to ours are likely to be found.     

Perturbations by the oblateness of the Earth and by the planets in the motion of the Moon

Perturbations in the motion of the Moon are computed for the effect by the oblateness of the Earth and for the indirect effect of planets. Based on Delaunay's analytical solution of the main problem, the computations are performed by a method of Fourier series operation. The effect of the oblateness of the Earth is obtained to the second order, partly adopting an analytical evaluation. Both in longitude and latitude are found a few terms whose coefficient differs from the current lunar ephemeris based on Brown's theory by about 0.01. While, concerning the indirect effect of planets, several periodic terms in the current ephemeris seem to have errors reaching 0.05.As for the secular variations of and due to the figure of the Earth and the indirect effect of planets, the newly-computed values agree within 1/cy with Brown's results reduced to the same values of the parameters. Further, the accelerations in the mean longitude, and caused by the secular changes in the eccentricity of the Earth's orbite and in the obliquity of the ecliptic are obtained. The comparison with Brown shows an agreement within 0.3/cy² for the former cause and 0.02/cy² for the latter. An error is found in the argument of the principal term for the perturbations due to the ecliptic motion in the current ephemeris.Proceedings of the Conference on Analytical Methods and Ephemerides: Theory and Observations of the Moon and Planets. Facultés universitaires Notre Dame de la Paix, Namur, Belgium, 28–31 July, 1980.     

On the model of the accumulation of the moon compatible with the data on the composition and the age of lunar rocks

It is suggested that the overall early melting of the lunar surface is not necessary for the explanation of facts and that the structure of highlands is more complicated than a solidified anorthositic ‘plot’. The early heating of the interior of the Moon up to 1000K is really needed for the subsequent thermal history with the maximum melting 3.5 × 10⁹ yr ago, to give the observed ages for mare basalts. This may be considered as an indication that the Moon during the accumulation retained a portion of its gravitational energy converted into heat, which may occur only at rapid processes. A rapid (t < 10³ yr) accretion of the Moon from the circumterrestrial swarm of small particles would give necessary temperature, but it is not compatible with the characteristic time 10⁸ yr of the replenishment of this swarm which is the same as the time-scale of the accumulation of the Earth. It is shown that there were conditions in the circumterrestial swarm for the formation at a first stage of a few large protomoons. Their number and position is evaluated from the simple formal laws of the growth of satellites in the vicinity of a planet. Such ‘systems’ of protomoons are compared with the observed multiple systems, and the conclusion is reached that there could have been not more than 2–3 large protomoons with the Earth. The tidal evolution of protomoon orbits was short not only for the present value of the tidal phase-lag but also for a considerably smaller value. The coalescence of protomoons into a single Moon had to occur before the formation of the observed relief on the Moon. If we accept the age 3.9 × 10⁹ yr for the excavation of the Imbrium basin and ascribe the latter to the impact of an Earth satellite, this collision had to be roughly at 30R, whereR is the radius of the Earth, because the Moon at that time had to be somewhere at this distance. Therefore, the protomoons had to be orbiting inside 20–25R, and their coalescence had to occur more than 4.0x10⁹ yr ago. The energy release at coalescence is equivalent to several hundred degrees and even 1000 K. The process is very rapid (of the order of one hour). Therefore, the model is valid for the initial conditions of the Moon.     

On the theory of the oblateness of the Sun

In this paper we first emphasize why it is important to know the successive zonal harmonics of the Sun's figure with high accuracy: mainly fundamental astrometry, helioseismology, planetary motions and relativistic effects. Then we briefly comment why the Sun appears oblate, going back to primitive definitions in order to underline some discrepancies in theories and to emphasize again the relevant hypotheses. We propose a new theoretical approach entirely based on an expansion in terms of Legendre's functions, including the differential rotation of the Sun at the surface. This permits linking the two first spherical harmonic coefficients (J ₂ and J ₄) with the geometric parameters that can be measured on the Sun (equatorial and polar radii). We emphasize the difficulties in inferring gravitational oblateness from visual measurements of the geometric oblateness, and more generally a dynamical flattening. Results are given for different observed rotational laws. It is shown that the surface oblateness is surely upper bounded by 11 milliarcsecond. As a consequence of the observed surface and sub-surface differential rotation laws, we deduce a measure of the two first gravitational harmonics, the quadrupole and the octopole moment of the Sun: J ₂=−(6.13±2.52)×10⁻⁷ if all observed data are taken into account, and respectively, J ₂=−(6.84±3.75)×10⁻⁷ if only sunspot data are considered, and J ₂=−(3.49±1.86)×10⁻⁷ in the case of helioseismic data alone. The value deduced from all available data for the octopole is: J ₄=(2.8±2.1)×10⁻¹². These values are compared to some others found in the literature. Supplementary material to this paper is available in electronic form at http://dx.doi.org/10.1023/A:1005238718479     

Accounting for the viscosity of the fluid core in the problem of the physical libration of the moon

A two-component theoretical model of the physical libration of the Moon in longitude is constructed with account taken of the viscosity of the core. In the new version, a hydrodynamic problem of motion of a fluid filling a solid rotating shell is solved. It is found that surfaces of equal angular velocity are spherical, and a velocity field of the fluid core of the Moon is described by elementary functions. A distribution of the internal pressure in the core is found. An angular momentum exchange between the fluid core and solid mantle is described by a third-order differential equation with a right-hand side. The roots of a characteristic equation are studied and the stability of rotation is proved. A libration angle as a function of time is found using the derived solution of the differential equation. Limiting cases of infinitely large and infinitely small viscosity are considered and an effect of lag of a libration phase from a phase of action of an external moment of forces is ascertained. This makes it possible to estimate the viscosity and sizes of the lunar fluid core from data of observations.     

On some problems concerning the calculation of the form of the magnetopause and the electric field on the magnetopause in the framework of the continuum medium model

In order to understand the reason of the existence of the electric field in the magnetosphere, and for the theoretical evaluation of its value, it is necessary to find the solution of the problem of determination of the magnetosphere boundary form in the frameworks of the continuum medium model which takes into account part of the magnetospheric plasma movement in supporting the magnetospheric boundary equilibrium. A number of problems for finding the distribution of the pressure, the density, the magnetic field and the electric field on the particular tangential discontinuity is considered in the case when the form of discontinuity is set (the direct problem) and a number of problems for finding the form of the discontinuity and the distribution of the above-mentioned physical quantities on the discontinuity is considered when the law of the change of the external pressure along the boundary is set (for example, with the help of the approximate Newton equation). The problem which is considered here, which deals with the calculation of the boundary form and with the calculation of the distribution of the corresponding physical quantities on the discontinuity of the 1st kind for the compressible fluid with the magnetic field with field lines which are perpendicular to the plane of the flow in question, concerns the last sort of problems. The comparison of the results of the calculation with the data in the equatorial cross-section of the magnetosphere demonstrates that the calculated form of the boundary, the value of the velocity of the return flow and the value of the electric field on the magnetopause, agree satisfactorily with the observational data.     

Third Integral and the Dynamics of the Galaxy in the Neighborhood of the Sun

Observational data on the dynamics of stars in the neighborhood of the sun indicate the existence of a third integral besides the integrals of the angular momentum and energy. The Poincaré integral is proposed as a third integral. The consequences of this assumption are derived and compared with available astrophysical data.