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Variation in the Flaring Potential of Different Sunspot Groups During Different Phases of Solar Cycles 23 and 24
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作者 Abha Singh Anurag Chaudhari +1 位作者 Gyaneshwar Sharma A.K.Singh 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2024年第2期144-153,共10页
In this present study,we have analyzed different types of X-ray solar flares(C,M,and X classes)coming out from different classes of sunspot groups(SSGs).The data which we have taken under this study cover the duration... In this present study,we have analyzed different types of X-ray solar flares(C,M,and X classes)coming out from different classes of sunspot groups(SSGs).The data which we have taken under this study cover the duration of 24 yr from 1996 to 2019.During this,we observed a total of 15015 flares(8417 in SC-23 and 6598 in SC-24)emitted from a total of 33780 active regions(21746 in SC-23 and 12034 in SC-24)with sunspot only.We defined the flaring potential or flare-production potential as the ratio of the total number of flares produced from a particular type of SSG to the total number of the same-class SSGs observed on the solar surface.Here we studied yearly changes in the flaring potential of different McIntosh class groups of sunspots in different phases of SC-23 and 24.In addition,we investigated yearly variations in the potential of producing flares by different SSGs(A,B,C,D,E,F,and H)during different phases(ascending,maximum,descending,and minimum)of SC-23 and 24.These are our findings:(1)D,E,and F SSGs have the potential of producing flares≥8 times greater than A,B,C and H SSGs;(2)The larger and more complex D,E,and F SSGs produced nearly 80%of flares in SC-23 and 24;(3)The A,B,C and H SSGs,which are smaller and simpler,produced only 20%of flares in SC-23 and 24;(4)The biggest and most complex SSGs of F-class have flaring potential 1.996 and 3.443 per SSG in SC-23 and 24,respectively.(5)The potential for producing flares in each SSG is higher in SC-24 than in SC-23,although SC-24 is a weaker cycle than SC-23.(6)The alterations in the number of flares(C+M+X)show different time profiles than the alterations in sunspot numbers during SC-23 and 24,with several peaks.(7)The SSGs of C,D,E,and H-class have the highest flaring potential in the descending phase of both SC-23 and 24.(8)F-class SSGs have the highest flaring potential in the descending phase of SC-23 but also in the maximum phase of SC-24. 展开更多
关键词 (sun:)sunspots-sun flares-sun activity-sun magnetic fields-sun filaments-prominences
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Solving the Olbers’s Paradox, Explaining the “Red-Shift”, and Challenging the Relativities by “Sun Matters Theory” and “Sun Model of Universe”, an Evolution of the Einstein’s Static Universe Model
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作者 Wanpeng Sun 《Natural Science》 2024年第2期7-18,共12页
Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used ... Olbers’s paradox, known as the dark night paradox, is an argument in astrophysics that the darkness of the night sky conflicts with the assumption of an infinite and eternal static universe. Big-Bang theory was used to partially explain this paradox, while introducing new problems. Hereby, we propose a better theory, named Sun Matters Theory, to explain this paradox. Moreover, this unique theory supports and extended the Einstein’s static universe model proposed by Albert Einstein in 1917. Further, we proposed our new universe model, “Sun Model of Universe”. Based on the new model and novel theory, we generated innovative field equation by upgrading Einstein’s Field Equation through adding back the cosmological constant, introducing a new variable and modifying the gravitationally-related concepts. According to the Sun Model of Universe, the dark matter and dark energy comprise the so-called “Sun Matters”. The observed phenomenon like the red shift is explained as due to the interaction of ordinary light with Sun Matters leading to its energy and frequency decrease. In Sun Model, our big universe consists of many universes with ordinary matter at the core mixed and surrounded with the Sun Matters. In those universes, the laws of physics may be completely or partially different from that of our ordinary universe with parallel civilizations. The darkness of night can be easily explained as resulting from the interaction of light with the Sun Matters leading to the sharp decrease in the light intensity. Sun Matters also scatter the light from a star, which makes it shining as observed by Hubble. Further, there is a kind of Sun Matters named “Sun Waters”, surrounding every starts. When lights pass by the sun, the Sun Waters deflect the lights to bend the light path. According to the Sun Model, it is the light bent not the space bent that was proposed in the theory of relativities. 展开更多
关键词 Olbers’s Paradox sun Matters Theory sun Model of Universe Einstein’s Universe Dark Mass
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Jovian Planet Influence on the Forcing of Sunspot Cycles
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作者 Fred J. Cadieu 《World Journal of Condensed Matter Physics》 CAS 2024年第1期1-9,共9页
The history of our solar system has been greatly influenced by the fact that there is a large gas giant planet, Jupiter that has a nearly circular orbit. This has allowed relics of the early solar system formation to ... The history of our solar system has been greatly influenced by the fact that there is a large gas giant planet, Jupiter that has a nearly circular orbit. This has allowed relics of the early solar system formation to still be observable today. Since Jupiter orbits the Sun with a period of approximately 12 years, it has always been thought that this could be connected to the nearly 11-year periodic peak in the number of sunspots observed. In this paper, the Sun and planets are considered to be moving about a center of mass point as the different planets orbit the Sun. This is the action of gravity that holds the solar system together. The center of mass for the Jupiter-Sun system actually lies outside the Sun. The four gas giant planets dominate such effects and the four gas giant Jovian planets can be projected together to determine an effective distance from the Sun’s center. Taken together these effects do seem to function as a sunspot forcing factor with a periodicity very close to 11 years. These predictions are made without consideration of any details of what is happening in the interior of the Sun. From these estimates, sunspot cycle 25 will be expected to peak in about September-October of 2025. Sunspot cycle 26 should peak in the year March of 2037. 展开更多
关键词 sun Cycles Solar System Formation JUPITER
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Dark Galaxies, Sun-Earth-Moon Interaction, Tunguska Event—Explained by WUM
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作者 Vladimir S. Netchitailo 《Journal of High Energy Physics, Gravitation and Cosmology》 CAS 2024年第2期836-853,共18页
Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fa... Great experimental results and observations achieved by Astronomy in the last decades revealed new unexplainable phenomena. Astronomers have conclusive new evidence that a recently discovered “dark galaxy” is, in fact, an object the size of a galaxy, made entirely of dark matter. They found that the speed of the Earth’s rotation varies randomly each day. 115 years ago, the Tunguska Event was observed, and astronomers still do not have an explanation of It. Main results of the present article are: 1) Dark galaxies explained by the spinning of their Dark Matter Cores with the surface speed at equator less than the escape velocity. Their Rotational Fission is not happening. Extrasolar systems do not emerge;2) 21-cm Emission explained by the self-annihilation of Dark Matter particles XIONs (5.3 μeV);3) Sun-Earth-Moon Interaction explained by the influence of the Sun’s and the Moon’s magnetic field on the electrical currents of the charged Geomagma (the 660-km layer), and, as a result, the Earth’s daylength varies;4) Tunguska Event explained by a huge atmospheric explosion of the Superbolide, which was a stable Dark Matter Bubble before entering the Earth’s atmosphere. 展开更多
关键词 World-Universe Model Dark Stars Dark Galaxies 21-cm Emission Formation of Macrostructures sun-Earth-Moon Interaction Tunguska Event Dark Matter
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The Decay Process of an α-configuration Sunspot
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作者 Yang Peng Zhi-Ke Xue +8 位作者 Xiao-Li Yan Aimee ANorton Zhong-Quan Qu Jin-Cheng Wang Zhe Xu Li-Heng Yang Qiao-Ling Li Li-Ping Yang Xia Sun 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2023年第2期73-81,共9页
The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR... The decay of sunspot plays a key role in magnetic flux transportation in solar active regions(ARs).To better understand the physical mechanism of the entire decay process of a sunspot,an α-configuration sunspot in AR NOAA 12411 was studied.Based on the continuum intensity images and vector magnetic field data with stray light correction from Solar Dynamics Observatory/Helioseismic and Magnetic Imager,the area,vector magnetic field and magnetic flux in the umbra and penumbra are calculated with time,respectively.Our main results are as follows:(1) The decay curves of the sunspot area in its umbra,penumbra,and whole sunspot take the appearance of Gaussian profiles.The area decay rates of the umbra,penumbra and whole sunspot are-1.56 MSH day^(-1),-12.61 MSH day^(-1) and-14.04 MSH day^(-1),respectively;(2) With the decay of the sunspot,the total magnetic field strength and the vertical component of the penumbra increase,and the magnetic field of the penumbra becomes more vertical.Meanwhile,the total magnetic field strength and vertical magnetic field strength for the umbra decrease,and the inclination angle changes slightly with an average value of about 20°;(3) The magnetic flux decay curves of the sunspot in its umbra,penumbra,and whole sunspot exhibit quadratic patterns,their magnetic flux decay rates of the umbra,penumbra and whole sunspot are-9.84 × 10^(19)Mx day^(-1),-1.59 × 10^(20)Mx day^(-1) and -2.60 × 10^(20)Mx day^(-1),respectively.The observation suggests that the penumbra may be transformed into the umbra,resulting in the increase of the average vertical magnetic field strength and the reduction of the inclination angle in the penumbra during the decay of the sunspot. 展开更多
关键词 sun atmosphere-sun magnetic fields-(sun:)sunspots
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Acoustic streaming and Sun's meridional circulation
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作者 Jose Manuel Valverde 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2016年第9期101-106,共6页
A vast number of physical processes involving oscillations of a bounded viscous fluid are relevantly influenced by acoustic streaming. When this happens a steady circulation of fluid develops in a thin boundary adjace... A vast number of physical processes involving oscillations of a bounded viscous fluid are relevantly influenced by acoustic streaming. When this happens a steady circulation of fluid develops in a thin boundary adjacent to the interface. Some examples are refracted sound waves, a fluid inside a spherical cavity undergoing torsional oscillations or a pulsating liquid droplet. Steady streaming around circular interfaces consists of a hemispherically symmetric recirculation of fluid from the equatorial plane to the polar axes closely resembling the meridional circulation pattern observed in the Sun's convection zone that determines the solar cycle. In this paper, it is argued that the acoustic pulsations exhibited by the Sun would lead to acoustic streaming in the boundary of the convection zone. A simple estimation using a typical dominant frequency of 3 mHz and the observed surface oscillation amplitude yields a steady streaming velocity Us - 10 m s^-1, which is on the order of the meridional circulation velocity observed in the Sun's convection zone. 展开更多
关键词 sun general -- sun helioseismology -- sun granulation -- sun oscillations -- sun fun-damental parameters -- sun activity
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A study of the relation between intensity oscillations and magnetic field parameters in a sunspot: Hinode observations 被引量:1
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作者 A.Raja Bayanna Shibu K.Mathew +2 位作者 Brajesh Kumar Rohan E.Louis P.Venkatakrishnan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2014年第11期1458-1468,共11页
We present properties of intensity oscillations of a sunspot in the photo- sphere and chromosphere using G band and Ca u H filtergrams from Hinode. Intensity power maps as function of magnetic field strength and frequ... We present properties of intensity oscillations of a sunspot in the photo- sphere and chromosphere using G band and Ca u H filtergrams from Hinode. Intensity power maps as function of magnetic field strength and frequency reveal reduction of power in the G band with an increase in photospheric magnetic field strength at all frequencies. In Ca II H, however, stronger fields exhibit more power at high frequen- cies, particularly in the 4.5-8.0 mHz band. Power distributions in different locations of the active region show that the oscillations in Ca II H exhibit more power compared to that of the G band. We also relate the power in intensity oscillations with differ- ent components of the photospheric vector magnetic field using near simultaneous spectro-polarimetric observations of the sunspot from the Hinode spectropolarime- ter. The photospheric umbral power is strongly anti-correlated with the magnetic field strength and its line-of-sight component but there is a good correlation with the trans- verse component. A reversal of this trend is observed in the chromosphere except at low frequencies (V≤ 1.5 mHz). The power in sunspot penumbrae is anti-correlated with the magnetic field parameters at all frequencies (1.0 ≤ v ≤ 8.0 mHz) in both the photosphere and chromosphere, except that the chromospheric power shows a strong correlation in the frequency range 3-3.5 mHz. 展开更多
关键词 sun photosphere -- sun chromosphere -- sun oscillations -- sun magnetic fields -- sun Hinode
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Low Dimensional Chaos from the Group Sunspot Numbers 被引量:2
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作者 Qi-Xiu Li Ke-Jun Li 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第3期435-440,共6页
We examine the nonlinear dynamical properties of the monthly smoothed group sunspot number Rg and find that the solar activity underlying the time series of Rg is globally governed by a low-dimensional chaotic attract... We examine the nonlinear dynamical properties of the monthly smoothed group sunspot number Rg and find that the solar activity underlying the time series of Rg is globally governed by a low-dimensional chaotic attractor. This finding is consistent with the nonlinear study results of the monthly Wolf sunspot numbers. We estimate the maximal Lyaponuv exponent (MLE) for the Rg series to be positive and to equal approximately 0.0187 ± 0.0023 (month^- 1). Thus, the Lyaponuv time or predictability time of the chaotic motion is obtained to be about 4.46 ± 0.5 years, which is slightly different with the predictability time obtained from Rz. However, they both indicate that solar activity forecast should be done only for a short to medium term due to the intrinsic complexity of the time behavior concerned. 展开更多
关键词 sun activity - sun sunspot - chaos - sun Wolf sunspot numbers
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The Emission Heights of Transition Region Lines in an Equatorial Coronal Hole and the Surrounding Quiet Sun 被引量:1
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作者 Hui Tian Li-Dong Xia +2 位作者 Jian-Sen He Bo Tan Shuo Yao 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2008年第6期732-742,共11页
Using the correlation between the radiance or Doppler velocity and the extrapolated magnetic field, we determined the emission heights of a set of solar transition region lines in an equatorial coronal hole and in the... Using the correlation between the radiance or Doppler velocity and the extrapolated magnetic field, we determined the emission heights of a set of solar transition region lines in an equatorial coronal hole and in the surrounding quiet Sun region. We found that for all of the six lower-transition-region lines, the emission height is about 4-5 Mm in the equatorial coronal hole, and around 2 Mm in the quiet Sun region. This result confirms the previous findings that plasma with different temperature can coexist at the same layer of transition region. In the quiet Sun region, the emission height of the upper-transition-region line Ne VIII is almost the same that of the lower-transition-region line, but in the coronal hole, it is twice as high. This difference reveals that the outflow of Ne VIII is a signature of solar wind in the coronal hole and is just a mass supply to the large loops in the quiet Sun. 展开更多
关键词 sun transition region sun magnetic fields sun solar wind sun UV radiation
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How much has the Sun influenced Northern Hemisphere temperature trends?An ongoing debate 被引量:1
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作者 Ronan Connolly Willie Soon +20 位作者 Michael Connolly Sallie Baliunas Johan Berglund C.John Butler Rodolfo Gustavo Cionco Ana G.Elias Valery M.Fedorov Hermann Harde Gregory W.Henry Douglas V.Hoyt Ole Humlum David R.Legates Sebastian Liming Nicola Scafetta Jan-Erik Solheim Laszlo Szarka Harry van Loon Victor M.Velasco Herrera Richard C.Willson 晏宏 Weijia Zhang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第6期131-198,共68页
In order to evaluate how much Total Solar Irradiance(TSI)has influenced Northern Hemisphere surface air temperature trends,it is important to have reliable estimates of both quantities.Sixteen different estimates of t... In order to evaluate how much Total Solar Irradiance(TSI)has influenced Northern Hemisphere surface air temperature trends,it is important to have reliable estimates of both quantities.Sixteen different estimates of the changes in TSI since at least the 19th century were compiled from the literature.Half of these estimates are"low variability"and half are"high variability".Meanwhile,five largely-independent methods for estimating Northern Hemisphere temperature trends were evaluated using:1)only rural weather stations;2)all available stations whether urban or rural(the standard approach);3)only sea surface temperatures;4)tree-ring widths as temperature proxies;5)glacier length records as temperature proxies.The standard estimates which use urban as well as rural stations were somewhat anomalous as they implied a much greater warming in recent decades than the other estimates,suggesting that urbanization bias might still be a problem in current global temperature datasets-despite the conclusions of some earlier studies.Nonetheless,all five estimates confirm that it is currently warmer than the late 19th century,i.e.,there has been some"global warming"since the 19th century.For each of the five estimates of Northern Hemisphere temperatures,the contribution from direct solar forcing for all sixteen estimates of TSI was evaluated using simple linear least-squares fitting.The role of human activity on recent warming was then calculated by fitting the residuals to the UN IPCC’s recommended"anthropogenic forcings"time series.For all five Northern Hemisphere temperature series,different TSI estimates suggest everything from no role for the Sun in recent decades(implying that recent global warming is mostly human-caused)to most of the recent global warming being due to changes in solar activity(that is,that recent global warming is mostly natural).It appears that previous studies(including the most recent IPCC reports)which had prematurely concluded the former,had done so because they failed to adequately consider all the relevant estimates of TSI and/or to satisfactorily address the uncertainties still associated with Northern Hemisphere temperature trend estimates.Therefore,several recommendations on how the scientific community can more satisfactorily resolve these issues are provided. 展开更多
关键词 sun:activity (sun:)solar terrestrial relations (sun:)sunspots sun:faculae plages
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A Statistical Study of Rapid Sunspot Structure Change Associated with Flares 被引量:1
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作者 Wei-Zhong Chen Chang Liu Hui Song Na Deng Chang-Yi Tan Hai-Min Wang 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2007年第5期733-742,共10页
We reported recently some rapid changes of sunspot structure in white-light (WL) associated with major flares. We extend the study to smaller events and present here results of a statistical study of this phenomenon... We reported recently some rapid changes of sunspot structure in white-light (WL) associated with major flares. We extend the study to smaller events and present here results of a statistical study of this phenomenon. In total, we investigate 403 events from 1998 May 9 to 2004 July 17, including 40 X-class, 174 M-class, and 189 C-class flares. By monitoring the structure of the flaring active regions using the WL observations from the Transition Region and Coronal Explorer (TRACE), we find that segments in the outer sunspot structure decayed rapidly right after many flares; and that, on the other hand, the central part of sunspots near the flare-associated magnetic neutral line became darkened. These rapid and permanent changes are evidenced in the time profiles of WL mean intensity and are not likely resulted from the flare emissions. Our study further shows that the outer sunspot structure decay as well as the central structure darkening are more likely to be detected in larger solar flares. For X-class flares, over 40% events show distinct sunspot structure change. For M- and C-class flares, this percentage drops to 17% and 10%, respectively. The results of this statistical study support our previously proposed reconnection picture, i.e., the flare-related magnetic fields evolve from a highly inclined to a more vertical configuration. 展开更多
关键词 sun activity -- sun flares -- sun magnetic fields -- sunspots
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Study of coexisting upstream solitary wave packet and downstream wakes induced by Diaoyu Dao and its affiliated islands detected by satellite sun glitter
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作者 Lina Cai Xiaoqi Jiang +5 位作者 Xiaojun Yan Yan Bai Jianqiang Liu Menghan Yu Rong Tang Jingjing Jiang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2023年第4期1-15,共15页
Taking the advantage of sun glitter(SG)observed from high-resolution satellites Gaofen-1(GF-1)and Gaofen-6(GF-6),a new method named Shield and Vortex 1-2(SAV1-2)for extracting spatial texture information from sun glit... Taking the advantage of sun glitter(SG)observed from high-resolution satellites Gaofen-1(GF-1)and Gaofen-6(GF-6),a new method named Shield and Vortex 1-2(SAV1-2)for extracting spatial texture information from sun glitter was established.Sea surface texture detail information around Diaoyu Dao and its affiliated islands was extracted using SAV1-2.Meanwhile,the dynamic characteristics of the water environment were analyzed by combining the water color,temperature and dynamic data.The results show the following information.(1)Stable westward shield effect and eastward Karman vortex streets,extracted from SG,appear upstream(westward)and downstream(eastward)of the Diaoyu Dao and its affiliated islands respectively.(2)The dominant direction of the Kuroshio Current in the Diaoyu Dao and its affiliated islands area is east,the Diaoyu Dao and its affiliated islands interacting with Kuroshio,inducing western shield and eastern shelter and wake.Furthermore,wave intervals of the shield in front of the island range from hundreds to thousands of metres,and extend wider than the island itself.(3)Combining with high-resolution sea surface temperature(SST)and chlorophyll a(Chl a)concentration,the directional changes of water color elements are mutually supported and proved with the stable shield(wave packet)effect in the west and vortex street effect in the east.The change of SST upstream of the island(western shield area)is not significant,the temperature in the downstream shelter area decreases slightly,and the SST in the downstream wake area shows a general trend of obvious decrease.The wake area is dominated by Karman vortex streets in shape,supplementing by vortices.The concentration of Chl a in the west shield of island is as low as that in downstream shelter area,while it increases significantly in the downstream wake area with shape in eddy or ribbon.(4)The SAV methods of extracting sea surface texture detail using SG can be widely used in different sea areas and water quality.This paper can provide reference for the protection and development of Diaoyu Dao and its affiliated islands and its surrounding waters.It is suggested that some kind of current buffer,such as marine wind farm,should be established in the western waters of Diaoyu Dao and its affiliated islands to protect the islands,and marine pasture should be developed in the downstream of eastern waters of Diaoyu Dao and its affiliated islands. 展开更多
关键词 sun glitter westward shield Diaoyu Dao and its affiliated islands GF-1/6
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The Sun’s Rotation Appears Differential plus Other New Views
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作者 Salah Abunaieb 《Natural Science》 CAS 2023年第4期167-178,共12页
This is a fresh perspective on the sun that considers its huge spherical size in relation to the finite speed of light. The sun is so extended that it takes light approximately 2.32 seconds to travel from the plane of... This is a fresh perspective on the sun that considers its huge spherical size in relation to the finite speed of light. The sun is so extended that it takes light approximately 2.32 seconds to travel from the plane of the solar limb to the plane tangential to the sun at the solar disc’s center. The aforementioned information is utilized in this study to support the new viewpoints. Firstly, it is shown that the solar disc is a simultaneous view of successively emitted coaxial spherical circles. Secondly, despite the fact that the sun is gaseous, it is thought to revolve completely as a rigid body at a fixed angular speed, yet an observer on Earth sees it rotate differentially. In a simple mathematical approach, it is found that the sun’s rotational speed apparently decreases with latitude. Thirdly, a qualitative examination of how we observe simultaneous whole-surface brightness changes of the sun and sunlike stars indicates that such changes would appear to spread out radially from the center of the solar disc. 展开更多
关键词 sun Differential Rotation Solar Radius Solar Disc Speed of Light Special Theory of Relativity Fading Stars
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Signature of high-order azimuthal MHD body modes in sunspot's low atmosphere
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作者 Ding Yuan 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2015年第9期1449-1454,共6页
The five-minute oscillations inside sunspots appear to be the absorption of the solar p-mode. It is a potential tool to probe a sunspot's sub-structure. We studied the collective properties of five-minute oscillation... The five-minute oscillations inside sunspots appear to be the absorption of the solar p-mode. It is a potential tool to probe a sunspot's sub-structure. We studied the collective properties of five-minute oscillations in the power and phase distribution at the sunspot's umbra-penumbra boundary. The azimuthal distributions of the power and phase of five-minute oscillations enclosing a sunspot's umbra were obtained with images taken with the Solar Dynamics Observatory/Atmospheric Imaging Assembly (SDO/AIA). The azimuthal modes were quantified with periodogram analysis and justified with significance tests. The azimuthal nodal structures in an approximately ax- ially symmetric sunspot AR 11131 (2010 Dec 08) were investigated. Mode numbers ra = 2, 3, 4, 7, 10 were obtained in both 1700 A and 1600A bandpasses. The 1600A channel also revealed an extra mode at m = 9. In the upper atmosphere (304 A), fewer modes were detected at m = 3, 4, 7. The azimuthal modes in the sunspot's low atmo- sphere could be interpreted as high-order azimuthal MHD body modes. They were detected in the power and phase of the five-minute oscillations in sunspot AR 11131 with SDO/AIA data. Fewer modes were detected in the sunspot's upper atmosphere. 展开更多
关键词 sun atmosphere - sun UV radiation -- sun sunSPOTS
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Periodic variation and phase analysis of grouped solar flare with sunspot activity
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作者 Hui Deng Ying Mei Feng Wang 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第2期75-84,共10页
Studies on the periodic variation and the phase relationship between different solar activity indicators are useful for understanding the long-term evolution of solar activity cycles.Here we report the statistical ana... Studies on the periodic variation and the phase relationship between different solar activity indicators are useful for understanding the long-term evolution of solar activity cycles.Here we report the statistical analysis of grouped solar flare(GSF) and sunspot number(SN) during the time interval from January 1965 to March 2009.We find that,(1) the significant periodicities of both GSF and SN are related to the differential rotation periodicity,the quasi-biennial oscillation(QBO),and the eleven-year Schwabe cycle(ESC),but the specific values are not absolutely identical;(2) the ESC signal of GSF lags behind that of SN with an average of 7.8 months during the considered time interval,which implies that the systematic phase delays between GSF and SN originate from the inter-solar-cycle signal.Our results may provide evidence about the storage of magnetic energy in the corona. 展开更多
关键词 sun:sunspots sun:flares sun:activity sun:magnetic fields
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SunStone公司接收了中国造环保型无限级远征游轮
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作者 刘昭青(编译) 《航海》 2023年第2期23-23,共1页
美国远征游轮船东太阳石船舶(Sunstone Ships),即太阳石海事集团(SunStone Maritime Group)的子公司已接收2艘生态友好型无限级(Infinity-class)远征游轮“Ocean Odyssey”号和“Sylvia Earle”号。该海洋信天翁(Ocean Albatros)级第六... 美国远征游轮船东太阳石船舶(Sunstone Ships),即太阳石海事集团(SunStone Maritime Group)的子公司已接收2艘生态友好型无限级(Infinity-class)远征游轮“Ocean Odyssey”号和“Sylvia Earle”号。该海洋信天翁(Ocean Albatros)级第六艘远征游轮的龙骨于2022年1月铺设。该无限级船舶长104 m,宽18 m,吃水5.1 m,载客量130~200人,船员容量85~115人。 展开更多
关键词 载客量 游轮 生态友好型 sun
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Magnetic non-potentiality on the quiet Sun and the filigree 被引量:3
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作者 Meng Zhao Jing-Xiu Wang Chun-Lan Jin Gui-Ping Zhou 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2009年第8期933-944,共12页
From the observed vector magnetic fields by the Solar Optical Telescope/ Spectro-Polarimeter aboard the satellite Hinode, we have examined whether or not the quiet Sun magnetic fields are non-potential, and how the G-... From the observed vector magnetic fields by the Solar Optical Telescope/ Spectro-Polarimeter aboard the satellite Hinode, we have examined whether or not the quiet Sun magnetic fields are non-potential, and how the G-band filigrees and Ca II network bright points (NBPs) are associated with the magnetic non-potentiality. A sizable quiet region in the disk center is selected for this study. The new findings by the study are as follows. (1) The magnetic fields of the quiet region are obviously non-potential. The region-average shear angle is 40°, the average vertical current is 0.016A m^-2, and the average free magnetic energy density, 2.7× 10^2erg cm^-3. The magnitude of these non-potential quantities is comparable to that in solar active regions. (2) There are overall correlations among current helicity, free magnetic energy and longitudinal fields. The magnetic non-potentiality is mostly concentrated in the close vicinity of network elements which have stronger longitudinal fields. (3) The filigrees and NBPs are magnetically characterized by strong longitudinal fields, large electric helicity, and high free energy density. Because the selected region is away from any enhanced network, these new results can generally be applied to the quiet Sun. The findings imply that stronger network elements play a role in high magnetic non-potentiality in heating the solar atmosphere and in conducting the solar wind. 展开更多
关键词 sun magnetic fields -- sun photosphere -- sun network bright point
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The causality between the rapid rotation of a sunspot and an X3.4 flare 被引量:3
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作者 Xiao-Li Yan Zhong-Quan Qu +2 位作者 Cheng-Lin Xu Zhi-Ke Xue De-Fang Kong 《Chinese Journal of Astronomy and Astrophysics》 CSCD 2009年第5期596-602,共7页
Using multi-wavelength data of Hinode, the rapid rotation of a sunspot in active region NOAA 10930 is studied in detail. We found extraordinary counterclockwise rotation of the sunspot with positive polarity before an... Using multi-wavelength data of Hinode, the rapid rotation of a sunspot in active region NOAA 10930 is studied in detail. We found extraordinary counterclockwise rotation of the sunspot with positive polarity before an X3.4 flare. From a series of vector magnetograms, it is found that magnetic force lines are highly sheared along the neutral line accompanying the sunspot rotation. Furthermore, it is also found that sheared loops and an inverse S-shaped magnetic loop in the corona formed gradually after the sunspot rotation. The X3.4 flare can be reasonably regarded as a result of this movement. A detailed analysis provides evidence that sunspot rotation leads to magnetic field lines twisting in the photosphere. The twist is then transported into the corona and triggers flares. 展开更多
关键词 sun sunspots - sun flares - sun magnetic fields
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Sun-Earth connection event of super geomagnetic storm on 2001 March 31:the importance of solar wind density 被引量:1
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作者 Li-Bin Cheng Gui-Ming Le Ming-Xian Zhao 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2020年第3期122-128,共7页
An X1.7 flare at 10:15 UT and a halo CME with a projected speed of 942 km s-1 erupted from NOAA solar active region 9393 located at N20 W19,which were observed on 2001 March 29.When the CME reached the Earth,it trigge... An X1.7 flare at 10:15 UT and a halo CME with a projected speed of 942 km s-1 erupted from NOAA solar active region 9393 located at N20 W19,which were observed on 2001 March 29.When the CME reached the Earth,it triggered a super geomagnetic storm(hereafter super storm).We find that the CME always moved towards the Earth according to the intensity-time profiles of protons with different energies.The solar wind parameters responsible for the main phase of the super storm occurred on 2001 March 31 are analyzed while taking into account the delayed geomagnetic effect of solar wind at the L1 point and using the SYM-H index.According to the variation properties of SYM-H index during the main phase of the super storm,the main phase of the super storm is divided into two parts.A comparative study of solar wind parameters responsible for two parts shows the evidence that the solar wind density plays a significant role in transferring solar wind energy into the magnetosphere,besides the southward magnetic field and solar wind speed. 展开更多
关键词 sun CORONAL mass ejections(CMEs)-sun solar-terrestrial relations--sun solar wind
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Predicting the 25th solar cycle using deep learning methods based on sunspot area data 被引量:1
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作者 Qiang Li Miao Wan +2 位作者 Shu-Guang Zeng Sheng Zheng Lin-Hua Deng 《Research in Astronomy and Astrophysics》 SCIE CAS CSCD 2021年第7期290-298,共9页
It is a significant task to predict the solar activity for space weather and solar physics. All kinds of approaches have been used to forecast solar activities, and they have been applied to many areas such as the sol... It is a significant task to predict the solar activity for space weather and solar physics. All kinds of approaches have been used to forecast solar activities, and they have been applied to many areas such as the solar dynamo of simulation and space mission planning. In this paper, we employ the long-shortterm memory(LSTM) and neural network autoregression(NNAR) deep learning methods to predict the upcoming 25 th solar cycle using the sunspot area(SSA) data during the period of May 1874 to December2020. Our results show that the 25 th solar cycle will be 55% stronger than Solar Cycle 24 with a maximum sunspot area of 3115±401 and the cycle reaching its peak in October 2022 by using the LSTM method. It also shows that deep learning algorithms perform better than the other commonly used methods and have high application value. 展开更多
关键词 sun:activity sun:solar cycle prediction sun:sunspot area Method:deep neural network
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