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云南天文台抚仙湖老鹰地太阳观测基地处于小江断裂带两侧分支的控制之下,但该基地址点的地质构造未见断裂错动.址点之东5000m,北1000m,南1500m,P1-P2β-C等地层未见缺失,组成由P2β玄武岩为核,P1、c等地层为翼的向斜构造.因此,该地块是断裂带中相对稳定的地质小块体,址点的地层为P1虎斑状灰岩、白云岩夹白云质灰岩是溶蚀岩层.应注意和防范抚仙湖水体的浪蚀对石灰岩本体的溶蚀等潜在的地质缺陷.虽说抚仙湖老鹰地太阳观测基地所处地块是地震活动带中相对稳定的地质块体,但它不能脱离小江断裂带西侧分支的控制,因此,在基建规划和实施中应作抗Ⅷ度地震的技术防范. 相似文献
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1990年2月10日在江苏太仓发生了M2＝5级的地震，在震前120天左右，离震中约60公里的上海天台光电中星仪的时间结果开始呈现显的异常现象。本分析结果进一步证实，测定地球自转运动的天光学观测技术是和预报区域性地震的一种手段。 相似文献
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白日视宁度监测仪和在抚仙湖的初步观测结果 总被引：1，自引：1，他引：0
报导了用南方基地云南天文台太阳差分像运动视宁度监测仪和美国国立太阳天文台的太阳闪烁仪,在云南省澄江县抚仙湖老鹰地红外太阳塔选址点进行的对比观测,简要地介绍了这两种视宁度测量方法的原理,对观测的初步结果进行了分析。 相似文献
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杨志根 《中国科学院上海天文台年刊》2008,(1)
根据中国大陆地壳运动GPS的观测结果,初步估计了沿四川龙门山断层带西北-东南两侧断层间东南向的聚敛率,并与2008年5月12日发生在四川汶川县的Ms8.0级特大地震触发产生的沿龙门山断层带的水平向破裂位移的相应分布进行了比较,结果证实,如同2004年苏门答腊-安达曼岛地震引起的地壳破裂滑行位移与板块间的聚敛率的关系一样,汶川Ms8.0级地震引起的近300km长的龙门山断层破裂位移分布与断层间的聚敛率大小密切相关。根据在龙门山断裂带沿带区域断层间每年几毫米量级的聚敛率结果和汶川Ms8.0级地震引起的逆冲位移观测结果,可估计得到龙门山断层带断层间聚敛应力的累积时间约为数百年至近千年,这个时间尺度与区域性特大地震发生的时间分布基本吻合。 相似文献
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主要介绍了抚仙湖1 m新真空太阳望远镜(the 1-meter New Vacuum Solar Telescope,NVST)6 m水平式近红外光谱仪的安装过程和实测结果。主要讨论内容是光路设计特点、光学系统的装调以及利用该光谱仪对活动区NOAA 11662黑子进行的初步近红外光谱实测(波长1.56μm附近)。成功观测到由黑子强磁场造成的Fe I 1.56μm谱线裂变现象,并初步估算了磁场强度。该光谱的成功装调和使用,充分实现了对9 m光谱仪光学系统的整体检测,为9 m光谱仪的安装调试提供了宝贵的经验和参考。 相似文献
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日月影响与云南未来地震趋势研究 总被引：1，自引：0，他引：1
详细分析了20世纪云南强震群体盛衰的天文背景,文中指出月亮白赤交角变化产生的交点潮[1]可能是影响地震长周期活动的一个原因。分析结果表明,20世纪以来云南的4个M≥6.7级强震活跃期有3个始发于月亮白赤交角极大年或其次年,仅第一个地震活跃期不是如此,所以总概率达80%。另外,无论太阳活动还是地震活动均存在11年的准周期,据此,作者利用20世纪云南历年最大地震的震级作了4组11年周期的外推,估计了下一个地震活跃期首发地震的时间和震级。综括上述2个天文条件,根据目前月亮白赤交角变化与太阳活动形势,我们认为云南下一个地震活跃期可能开始于2006/2007年,并可能持续活动至2015年,该期间将有较多M≥6.7级地震发生,将构成云南又一个地震重灾期。文中还对强震首发地点作了预测估计。 相似文献
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日月影响与云南未来地震趋势研究 总被引：5，自引：0，他引：5
详细分析了20世纪云南强震群体盛衰的天文背景，文中指出月亮白赤交角变化产生的交点潮可能是影响地震长周期活动的一个原因。分析结果表明，20世纪以来云南的4个M≥6．7级强震活跃期有3个始发于月亮白赤交角极大年或其次年，仅第一个地震活跃期不是如此，所以总概率达80％。另外，无论太阳活动还是地震活动均存在11年的准周期，据此，作者利用20世纪云南历年最大地震的震级作了4组11年周期的外推，估计了下一个地震活跃期首发地震的时间和震级。综括上述2个天文条件，根据目前月亮白赤交角变化与太阳活动形势，我们认为云南下一个地震活跃期可能开始于2006／2007年，并可能持续活动至2015年，该期间将有较多M≥6．7级地震发生，将构成云南又一个地震重灾期。文中还对强震首发地点作了预测估计。 相似文献
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顾震年 《中国科学院上海天文台年刊》1999,(20):23-28
采用Harvard目录中1977－1994年及1960－1993年间的地震有关参数,由Dahlen理论和Lam-beck推出的有关公式估计了地震引起地球轴向惯性矩的累积变化,分析了地震和El Nino事件之间的联系,特别是震级大于5级地地震引起的位错所产生的地球轴向惯性矩的变化会有一个跳跃,这个跳跃的El Nino事件有着很好的对应关系。 相似文献
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C. M. Andreazza E. P. Marinho P. D. Singh † 《Monthly notices of the Royal Astronomical Society》2006,372(4):1653-1656
The rate coefficients for the formation of carbon monophosphide (CP) and silicon monophosphide (SiP) by radiative association are estimated for temperatures ranging from 300 to 14 100 K. In this temperature range, the radiative association rate coefficients are found to vary from 1.14 × 10−18 to 1.62 × 10−18 cm3 s−1 and from 3.73 × 10−20 to 7.03 × 10−20 cm3 s−1 for CP and SiP, respectively. In both cases, rate coefficients increase slowly with the increase in temperature. 相似文献
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DDO photometry and metallic abundances of E and SO galaxies and globular clusters of the LMC and SMC
Horacio A. Dottori Miriani G. Pastoriza Eduardo L. D. Bica 《Astrophysics and Space Science》1983,91(1):79-91
Metallicity of 8 E and SO galaxies as well as that of red globulars of the LMC and SMC were obtained by means of DDO integrated photometry calibrated with galactic globular clusters (Bica and Pastoriza, 1983; hereafter referred to as Paper I). A correction was obtained in order to reduce the colors of the galaxies to zero redshift. The relation metallicity vsM V for the galaxies is analyzed (adding to our sample the observations of McClure and Van den Bergh, 1968; and Faber, 1973a). For the Magellanic Clouds we found metallicity ranging from intermediate to poor. 相似文献
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Dale P. Cruikshank 《Icarus》1977,30(1):224-230
Thermal radiation has been detected from four asteroids of the Trojan group, and J6 and J7, the brightest of the outer satellites of Jupiter. The six objects all have exceedingly low geometric albedos of 0.02 or 0.03 according to calculations based on their known visual brightness and the measured thermal fluxes. 624 Hektor, the largest object studied here, has a radius of 110 ± 20 km, though the exact shape of this body is in question. While the sample observed in this work is small (the total number of Trojans larger than 0.25 km in radius is about 1000), the fact that all four studied have similarly low albedos suggests that this property is characterisic of the Trojans and at least two of the outer members of Jupiter's retinue of satellites. The low surface albedo of the Trojans may preclude the proposed origin of the Jovian group of comets among these bodies according to E. Rabe. Updated tables of the dimensions of all the Jovian satellites are given. 相似文献
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Both Uranus and Neptune are thought to have strong zonal winds with velocities of several 100 m s−1. These wind velocities, however, assume solid-body rotation periods based on Voyager 2 measurements of periodic variations in the planets’ radio signals and of fits to the planets’ magnetic fields; 17.24 h and 16.11 h for Uranus and Neptune, respectively. The realization that the radio period of Saturn does not represent the planet’s deep interior rotation and the complexity of the magnetic fields of Uranus and Neptune raise the possibility that the Voyager 2 radio and magnetic periods might not represent the deep interior rotation periods of the ice giants. Moreover, if there is deep differential rotation within Uranus and Neptune no single solid-body rotation period could characterize the bulk rotation of the planets. We use wind and shape data to investigate the rotation of Uranus and Neptune. The shapes (flattening) of the ice giants are not measured, but only inferred from atmospheric wind speeds and radio occultation measurements at a single latitude. The inferred oblateness values of Uranus and Neptune do not correspond to bodies rotating with the Voyager rotation periods. Minimization of wind velocities or dynamic heights of the 1 bar isosurfaces, constrained by the single occultation radii and gravitational coefficients of the planets, leads to solid-body rotation periods of ∼16.58 h for Uranus and ∼17.46 h for Neptune. Uranus might be rotating faster and Neptune slower than Voyager rotation speeds. We derive shapes for the planets based on these rotation rates. Wind velocities with respect to these rotation periods are essentially identical on Uranus and Neptune and wind speeds are slower than previously thought. Alternatively, if we interpret wind measurements in terms of differential rotation on cylinders there are essentially no residual atmospheric winds. 相似文献
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Amir Babak Aazami Priyamvada Natarajan 《Monthly notices of the Royal Astronomical Society》2006,372(4):1692-1698
Gravitational lensing of a background source by a foreground galaxy lens occasionally produces four images of the source. The cusp and the fold relations impose conditions on the ratios of magnifications of these four-image lenses. In this theoretical investigation, we explore the sensitivity of these relations to the presence of substructure in the lens. Starting with a smooth lens potential, we add varying amounts of substructure, while keeping the source position fixed, and find that the fold relation is a more robust indicator of substructure than the cusp relation for the images. This robustness is independent of the detailed spatial distribution of the substructure, as well as of the ellipticity of the lensing potential and the presence of external shear. 相似文献
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R. Rummel 《Earth, Moon, and Planets》2004,94(1-2):103-111
Planetology serves the understanding on the one hand of the solar system and on the other hand, for investigating similarities
and differences, of our own planet. While observational evidence about the outer planets is very limited, substantial datasets
exist for the terrestrial planets. Radar and optical images and detailed models of gravity and topography give an impressive
insight into the history, composition and dynamics of moon and planets. However, there exists still significant lack of data.
It is therefore recommended to equip all future satellite missions to the moon and to planets with full tensor gravity gradiometers
and radar altimeters. 相似文献
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B. P. GLASS D. W. MUENOW B. F. BOHOR G. P. MEEKER 《Meteoritics & planetary science》1997,32(3):333-341
Abstract— An examination of data collected over the last 30 years indicates that the percent of glass fragments vs. whole splash forms in the Cenozoic microtektite strewn fields increases towards the source crater (or source region). We propose that this is due to thermal stress produced when tektites and larger microtektites fall into water near the source crater while still relatively hot (>1150 °C). We also find evidence (low major oxide totals, frothing when melted) for hydration of most of the North American tektite fragments and microtektites found in marine sediments. High-temperature mass spectrometry indicates that these tektite fragments and microtektites contain up to 3.8 wt% H2O. The H2O-release behavior during the high-temperature mass-spectrometric analysis, plus high CI abundances (0.05 wt%), indicate that the North American tektite fragments and microtektites were hydrated in the marine environment (i.e., the H2O was not trapped solely on quenching from a melt). The younger Ivory Coast and Australasian microtektites do not exhibit much evidence of hydration (at least not in excess of 0.5 wt% H2O); this suggests that the degree of hydration increases with age. In addition, we find that some glass spherules (with <65 wt% SiO2) from the upper Eocene clinopyroxene-bearing spherule layer in the Indian Ocean have palagonitized rims. These spherules appear to have been altered in a similar fashion to the splash form K/T boundary spherules. Thus, our data indicate that tektites and microtektites that generally contain >65 wt% SiO2 can undergo simple hydration in the marine environment, while impact glasses (with <65 wt% SiO2) can also undergo palagonitization. 相似文献
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V. Bumba 《Solar physics》1996,169(2):303-312
We have compiled the results of our long-term studies of the local magnetic field and its activity development, derived from investigating sunspot group evolution, photoelectrically measured longitudinal magnetic and velocity fields, and measurements of sunspot proper motions. We estimate certain regularities according to which the magnetic and velocity fields, and photospheric, as well as chromospheric activities develop. We speculate about the physical background of such processes.Dedicated to Cornelis de Jager 相似文献