共查询到20条相似文献，搜索用时 31 毫秒
1.
Christiane Helling R. Giles Harrison Farideh Honary Declan A. Diver Karen Aplin Ian Dobbs-Dixon Ute Ebert Shu-ichiro Inutsuka Francisco J. Gordillo-Vazquez Stuart Littlefair 《Surveys in Geophysics》2016,37(4):705-756
Detailed observations of the solar system planets reveal a wide variety of local atmospheric conditions. Astronomical observations have revealed a variety of extrasolar planets none of which resembles any of the solar system planets in full. Instead, the most massive amongst the extrasolar planets, the gas giants, appear very similar to the class of (young) brown dwarfs which are amongst the oldest objects in the Universe. Despite this diversity, solar system planets, extrasolar planets and brown dwarfs have broadly similar global temperatures between 300 and 2500 K. In consequence, clouds of different chemical species form in their atmospheres. While the details of these clouds differ, the fundamental physical processes are the same. Further to this, all these objects were observed to produce radio and X-ray emissions. While both kinds of radiation are well studied on Earth and to a lesser extent on the solar system planets, the occurrence of emissions that potentially originate from accelerated electrons on brown dwarfs, extrasolar planets and protoplanetary disks is not well understood yet. This paper offers an interdisciplinary view on electrification processes and their feedback on their hosting environment in meteorology, volcanology, planetology and research on extrasolar planets and planet formation. 相似文献
2.
最近,一些西方资产阶级学者提出“九星成线”灾难说:当太阳系九颗行星在太阳同侧排成一线时,将会骤然“刹住”地球自转,引起灾难性的大地震。本文对这种错误观点进行了批判。 根据中国二千七百多年历史地震的丰富记载,七级以上的大地震共发生过一百二十多次,同期“九星成线”有十五次,可这百余次大震没有一次发生在“九星成线”的年份上。迄今为止,世界上最大的一次地震,既与“九星成线”无关,也并未“摧毁地球”。对地球引力的主要影响来自太阳和月球,其他行星影响总和的最大值,不过是月球的万分之一而已。地震是地球内部的一种矛盾运动,不能把行星间引力对某些地震的影响片面夸大加以绝对化。“九星成线”灾难说,缺乏事实根据,在科学上是说不通的。 这种错误观点的提出并非偶然,科学技术的发展总是为一定的政治路线服务的。早在我国西汉末年（公元一世纪初年）,孔孟之徒曾对这同一种自然现象宣扬过“五星联珠”吉祥说,妄图挽救反动奴隶制的崩溃。同儒家曲解自然现象的下场一样,西方资产阶级宣扬灾难说,欺骗人民,以掩盖资本主义世界的政治经济危机,也必然是完全徒劳的。 相似文献
3.
《Astronomy& Geophysics》2007,48(4):4.05-4.05
It's one thing to picture weather on other planets in the solar system, quite another to get any idea of conditions on planets orbiting other stars, but that is what researchers using the Spitzer Space Telescope have done. 相似文献
4.
G.P. Horedt 《Physics of the Earth and Planetary Interiors》1980,21(1):22-30
Analytical estimates for three important and general planetary heating processes, excluding radioactive heating, are presented: accretional heating, adiabatic compression and core formation. The relative importance of these processes appears to be as follows. Accretional heating is important for almost all planets and satellites including asteroid-size bodies. Heating due to core formation becomes important for objects which are similar to, or larger than the terrestrial planets. Compressional heating is important only for the outer cores and the envelopes of the giant planets, provided that they are heated, before compression, up to about 1000 K. 相似文献
5.
The paper addresses the interpretation of the geochemical laboratory experiments aimed at studying the differentiation of partially molten rocks in the terrestrial planets. These experiments simulate the early stages of material differentiation when the layers with the different chemical and petrological composition are formed in the planets. Density inversion which may arise at a certain stage of this process leads to the emergence of the Rayleigh–Taylor instability. The lifetime of this instability is estimated, and the different phases of its evolution are explored. It is shown that the laboratory experiments do not always adequately reproduce the nature of the physical processes which occur in the interior of the planets. The suggested methods are also used for interpreting the evolution of intrusions during their differentiation. The obtained results can be helpful in analyzing the intrusions for minerals. 相似文献
6.
T. Németh 《Pure and Applied Geophysics》1966,63(1):205-210
Summary According to the author the reason of the subsistence of the 11 years' sunspot cycle is to be found in the conjunction of the planets. As a result of the investigations it has been stated that from among the nine planets the joint tidal effect of Venus-Jupiter-Earth is a decisive factor in the variations of sunspot activity. The above three planets are every 10.4 years and 12.0 years respectively, in a close conjunction. The mean value (11.2 years) is in an almost full accordance with the average cycle-period. The fluctuations of the period of the cycle come from the fact that the planets' getting into approximately one line takes a different time within each cycle. This time delay is the cause of the stronger or weaker sunspot activity, and of the shorter or longer cycles. 相似文献
7.
行星运行都具有一定的周期性.近百年历次大震是在行星20,59,237年会合及合成与月回归下降时段内发震的.文内把近百年强震与当年天文年历及各大行星运行数据绘制地心距视赤经天象图,及5大行星黄经位置天象图,经过验证得出结论.供长期地震预报参考. 相似文献
8.
Crater ejecta: Markers of impact catastrophes 总被引：1，自引：0，他引：1
V. V. Shuvalov N. A. Artemieva M. Yu. Kuz’micheva T. V. Losseva V. V. Svettsov V. M. Khazins 《Izvestiya Physics of the Solid Earth》2012,48(3):241-255
The role of impact crater ejecta in the evolution of the Earth and Solar System planets is considered. Using the methods of
numerical modeling, the accretion and erosion of planets, the redistribution of planetary material due to impacts of large
cosmic bodies and related geospheric interactions, the asymmetrical deposition of ejecta around the crater rim, and the possibility
of nonballistic transportation of ejecta are analyzed. The influence of impact events on the Earth’s envelopes is compared
with the effects of volcanic eruptions. 相似文献
9.
10.
Fractionation between the metal and silicate components of objects in the inner solar system has long been recognized as a necessity in order to explain the observed density variations of the terrestrial planets and the H-group, L-group dichotomy of the ordinary chondrites. This paper discusses the densities of the terrestrial planets in light of current physical and chemical models of processes in the solar nebula. It is shown that the observed density trends in the inner solar system need not be the result of special fractionation processes, and that the densities of the planets may be direct results of simultaneous application of both physical and chemical restraints on the structure of the nebula, most notably the variation of temperature with heliocentric distance. The density of Mercury is easily attributed to accretion at temperatures so high that MgSiO3 is only partially retained but Fe metal is condensed. The densities of the other terrestrial planets are shown to be due to different degrees of retention of S, O and H as FeS, FeO and hydrous silicates produced in chemical equilibrium between condensates and solar-composition gases. It is proposed that Mercury and Venus Have cores of Fe0, Earth has a core of Fe0 containing substantial amounts of FeS, and Mars has a quite small core of FeS with more FeO in its mantle than in Earth's. Geophysical and geochemical consequences of these conclusions are discussed. 相似文献
11.
Acceleration of charged particles in magnetic field-aligned electric potential differences at Earth and at the outer planets in the solar system is summarized and its general importance in the Universe is briefly discussed.The role of field-aligned currents, driven by parallel electric fields, in causing filamentary structure in stellar atmospheres is briefly reviewed.The differences between auroral optical emissions at various planets are summarized.The important role of field-aligned potential differences in the generation of AKR and corresponding emissions from other objects is discussed.Finally, aurora-associated processes for ejection of planetary plasma into space are briefly reviewed. 相似文献
12.
David Le Conte 《Astronomy& Geophysics》2007,48(4):4.07-4.07
Eris, the planetary body formerly known as Xena, turns out to be the largest of the new class of dwarf planets. 相似文献
13.
Anthony Whitworth 《Astronomy& Geophysics》2000,41(6):6.18-6.19
Anthony Whitworth argues for a clear practical distinction between planets and stars – and an end to substellar objects. 相似文献
14.
Lewis Dartnell 《Astronomy& Geophysics》2005,46(1):1.12-1.13
Lewis Dartnell wonders how astronomers find life on this and other planets. After all, they do it on Star Trek with just a scanner… 相似文献
15.
《Astronomy& Geophysics》2008,49(1):1.06-1.06
Dust particles in a supernova remnant have been tracked to the supernova itself – an important step in understanding the formation of planets. 相似文献
16.
Since 1969, seismology has been extended beyond the Earth, and seismic sensors have been placed on the surface of other bodies of the solar system. A Lunar seismic network thus operated for the 8 years after 1969, with up to 4 stations, and detected some 1000 Moonquakes per year. A single seismic station was also operated on the Martian surface for 19 months since 1977. Unfortunately, it did not detect any Marsquakes, but produced useful information for future experiments. Remotesensing seismic experiments using Doppler shift observation have also been applied to Jupiter in the last two years and are beginning to return information on the normal modes. Planetary seismology is thus now well developed, and will provide increasing information on the structure and dynamics of the planets and bodies of the solar system. In this paper we review the state of the art in planetary seismology. For the terrestrial planets, we compare the seismic sources, structure and experiments on Earth, Moon and Mars. Such a comparison is useful in evaluating the design of past or future experiments. Results in the seismology of giant planets are also reviewed, stressing the connection between methods and theory. 相似文献
17.
《Astronomy& Geophysics》2008,49(1):1.05-1.05
Red dust around a young star could indicate the presence of complex organic molecules at an early stage in the evolution of planets. 相似文献
18.
Geomagnetism and Aeronomy - This study uses the evolution of a parameter introduced by the author that characterizes the relative position of planets: the daily average difference of the... 相似文献
19.
Makalkin A. B. Ziglina I. N. Artyushkova M. E. 《Izvestiya Physics of the Solid Earth》2019,55(1):87-101
Izvestiya, Physics of the Solid Earth - We consider the history of the development of the theory of the formation of the Earth and planets over 70 years with special emphasis placed on the... 相似文献
20.
Don Pollacco 《Astronomy& Geophysics》2005,46(1):1.19-1.22
Don Pollacco reviews progress so far on SuperWASP, a wide-field astronomy project designed to detect extrasolar planets and more, built with a lot of hard work – and a little help from eBay. 相似文献