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1.
中国虚拟天文台研发策略与重点 总被引：5，自引：3，他引：2
由于不同的天文和技术背景，不同的虚拟天文台项目采取了不同的研究策略。本文首先介绍了国际上几个典型虚拟天文台项目的研发目标和工作重点；然后讨论了包括中国虚拟天文台在内的小型虚拟天文台项目在研发方面的优势和劣势。中国虚拟天文台项目根据自身所处的具体情况确定自己将走应用路线，争取在某些领域取得突破，研发重点包括五个方面：China-VO系统平台建设、国内外天文数据的统一访问、现有天文工具的虚拟天文台集成、天文设备的虚拟天文台集成、虚拟天文台基础上的公众教育。 相似文献
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G. Soulie 《Earth, Moon, and Planets》1970,2(2):159-166
In order to improve our knowledge of the astronomical constants, great interest must be paid to accurate positions of major planets and their satellites. Likewise, accurate astrometry of the Moon on stellar background is essential to determine the ephemeris time. Both programs are pursued by Bordeaux Observatory. 相似文献
4.
John A. O'Keefe 《Astrophysics and Space Science》1972,16(2):201-211
A planet the size of the Earth or the Moon is much like a blast furnace; it produces slag-like rock floating on a mass of liquid metal. In the Earth, the mantle and crust are the slag, and the core is the liquid iron.In the Moon, there is clear chemical evidence that liquid iron was separated from the mass, but the Moon has no detectable iron core. This points to some kind of joint origin, which put the metallic iron in the Earth's core. For instance, the Moon might have been a detached part of the rocky matter of the Earth, as suggested by G. H. Darwin in the 1880's. But is is also clear, as Ringwood has pointed out, the there has been an enormous loss of volatiles from both Earth and Moon, but especially from the Moon. It may be that the Moon formed from a sediment-ring of small bodies detached somehow from the outer parts of the Earth, as Öpik has suggested.If tektites come from the Moon, then Darwin's suggestion is probably right; if they come from the Earth, then the Öpik-Ringwood sediment ring may be the origin.Paper presented at the AAAS Symposium on the Early History of the Earth and Moon in Philadelphia on 28 December 1971. 相似文献
5.
L. V. Morrison 《Earth, Moon, and Planets》1972,5(3-4):253-264
The results and methods of determining the secular accelerations of the Moon's orbital motion and the Earth's rotation from astronomical observations are critically reviewed. In particular, the effect on these results is considered should Spencer Jones' value for the secular acceleration of the Moon be revised. General relationships are deduced between these accelerations, the rate of dissipation of energy in the Earth and the fractional change in the rate of rotation of the Earth. It is shown that the theory of tidal torques alone does not completely account forany of the wide range of results for the retardation of the Earth deduced from astronomical observations.Presented to the NATO Advanced Study Institute on Lunar Studies, Patras, Greece, September 1971. 相似文献
6.
“干支回推法”是针对中国历史时期所特有的干支材料而设计的新天文年代学方法．以一组假设的材料为例,系统地给出了该方法的完整求解过程．指出该方法的优势在于准确高效,能有效地处理某些年代学难题．此外,除材料的公历日期外还能将当时的历法细节一同迭代解出． 相似文献
7.
L. V. Ksanfomality 《Solar System Research》2009,43(5):405-409
Images of the 280°–360°/0°–10° W longitude sector of Mercury’s surface produced from the results of recent ground-based astronomical
observations are presented. This sector remained beyond the imaging from the Messenger spacecraft in 2008. Vast dark regions, up to 1000 km in diameter, are adjacent to the S Basin in the west. The dark objects,
as well as the other large geomorphologic units found before in the 240°–360° W longitude sector from ground-based astronomical
observations, are probably asymmetrically distributed on Mercury’s surface similar to those observed in the other terrestrial
planets and the Moon. 相似文献
8.
It is generally accepted that the Earth-Moon separation is at present increasing due to tidal dissipation. Values for the corresponding lunar deceleration and the related slowing of the Earth's rotation are obtained from astronomical observations and by studies of ancient eclipses. Extrapolation of these values leads to a close approach of the Earth and Moon 1–3 b.y. BP. However, justification for such an extrapolation is required. It has been hypothesized that periodicities in the Precambrian stromatolites can be used to determine the number of solar days in a lunar month prior to 500 m.y. BP. These data combined with dynamic constraints on the number of solar days in a lunar month indicate a close approach of the Earth and Moon at 2.85 ± 0.25 b.y. BP. It is suggested that the mare volcanism on the Moon and high-temperature Archean volcanism on the Earth prior to this date were caused by tidal heating. It is also suggested that the strong tidal heating during a close approach could have contributed to the formation of the first living organisms. 相似文献
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Wang Shouguan 《Astrophysics and Space Science》1989,160(1-2):287-294
For the 1990's, plans for some astronomical facilities and related researchers are being carried out in China. In this report we describe in some details the plans of radio astronomical facilities, 150/220 cm Schmidt telescope, and experiments on porcelain mirror material.Paper presented at the Symposium on the JNLT and Related Engineering Developments, Tokyo, November 29–December 2, 1988. 相似文献
11.
M. P. Sinitsyn 《Earth, Moon, and Planets》2013,110(1-2):29-39
This article provides some astronomical background for a systematic study of the lunar regolith. The Moon, like other atmosphere-less bodies, is the subject to all kinds of cosmic radiation, which are imprinted in the lunar surface. Therefore, the study of the lunar regolith for signs of cosmic radiation can assist to trace the history of changes in these emissions over time. Mostly changes in the solar wind and galactic cosmic rays are very interesting at time intervals from a few tens of millions of years to several billion years. The paper develops the idea of paleoregolith, the possible location of which can be seen on the slopes of some craters (Euler, Bessel) in images obtained by camera of LRO spacecraft (LROC). Because of the complexities of placing a spacecraft on the slopes of craters, some other possible locations of paleoregolith are offered to consideration. To study the recent history of the evolution of the Moon and the inner planets (up to 200 million years) the stored information in impact and volcanic melts, which are widely represented in the LROC images, should be considered. 相似文献
12.
One of the main problems of selenodesy consists of the construction of a net of basic reference points on the surface of the Moon. At present there exist many catalogues containing the coordinates of selected objects on the Moon. These catalogues differ by the presence of both systematic and accidental errors.The investigations concerning the comparison of catalogues and the elucidation of their systematic differences are of very recent date. Various methods of interpretation of the systematic differences between catalogues have been proposed. Without an attempt to encompass the whole problem in what follows, we shall describe one method for comparative study of catalogues based on the theory of the deformation of continuous media. 相似文献
13.
Remote sensing of atmosphere is conventionally done via a study of extinction/scattering of light from natural (Sun, Moon) or artificial (laser) sources. Cherenkov emission from extensive air showers generated by cosmic rays provides one more natural light source distributed throughout the atmosphere. We show that Cherenkov light carries information on three-dimensional distribution of clouds and aerosols in the atmosphere and on the size distribution and scattering phase function of cloud/aerosol particles. Therefore, it could be used for the atmospheric sounding. The new atmospheric sounding method could be implemented via an adjustment of technique of imaging Cherenkov telescopes. The atmospheric sounding data collected in this way could be used both for atmospheric science and for the improvement of the quality of astronomical gamma-ray observations. 相似文献
14.
The main points are presented of a new hypothesis of the origin of the Earth—Moon system, developed on the basis of Savi's (1961) theory of the origin of rotation of celestial bodies. The cooling off and contraction due to gravitational attraction on vast particle systems, with the pushing out of electrons from atom shells result in a continually increasing density. Depending on the amount of mass, this pushing out can lead to the expulsion of electrons and the creation of a magnetic field by which a rotational motion is brought about. These conditions are satisfied for the Earth's mass and all larger masses. If the Earth and the Moon formed a unique body, the protoplanet, then once rotational motion had begun, the primeval spherical body must have taken the shape of a large Jacobi ellipsoid. New condensation followed, however no longer solely around the centre of the protoplanet, but also along the edge of the ellipsoid, the process leading to the creation of the dual Earth—Moon system. 相似文献
15.
The selenocentric coordinates of 263 craters and one mountain are given. The scale and orientation of the selenocentric coordinates system is determined by star-calibrated lunar photographs obtained with the long-focus horizontal telescope. The origin of the system is defined by the theory of the motion of the Moon. The physical libration is taken into account for the reduction of the coordinates system to the principal axes of the lunar inertia. The reference stars coordinates are reduced to the FK4 system. The position of the lunar mass centre is determined by LURE-2 theory, the rotation parameters are taken from the Migus tables (Migus, 1980). 相似文献
16.
夏商周断代工程及其天文学问题 总被引：1，自引：0，他引：1
《夏商周断代工程》由文献,考古,古文字,碳14测年和天文学待方面的专家联合攻关,致车于推进我国早期年代学研究的发展,天文学在五星聚合,三代大火,国外天象,仲康日食,夏小正,禹伐三苗,甲骨文天象,武王伐纣,天再旦,金文历谱,周代历法,计算中心等专题中起了主要或重要作用,天文方法确定的宾组月食,武王伐纣和天再旦年代被作为断代工程结论而采用,成为夏商周年的重要支撑点,铜器铭文中的朋相记录也是西周列王年代的重要依据。 相似文献
17.
In 1799 Laplace discovered that the three principal moments of the Moon are not in equilibrium with the Moon's current orbital and rotational state. Some authors suggested that the Moon may carry a fossil figure. More than 3 billion years ago, the liquid Moon was closer to the Earth and revolved faster. Then the Moon migrated outwards and its rotation slowed down. During the early stage of this migration, the Moon was continually subjected to tidal and rotational stretching and formed into an ellipsoid. Subsequently the Moon cooled down and solidified quickly. Eventually, the solid Moon's lithosphere was stable and as a result we may see the very early lunar figure. 相似文献
18.
Solar System Research - The construction of the trajectories for spacecraft return from the Moon to the Earth for delivering lunar soil to the polygon specified by the corresponding geographical... 相似文献
19.
C. B. Watts' charts of the marginal zone of the Moon have been put into the form of tables of rectangular co-ordinates of points along the contours. These co-ordinates were recorded automatically on paper tape and transferred, firstly to a magnetic tape, then secondly to an exchangeable-disc cartridge allowing random access to every chart. 相似文献
20.
I argue that science stands to benefit from the infrastructure developed to support a human space programme. By infrastructure
I mean all those facilities and capabilities which purely scientific budgets could never afford to develop, but which nevertheless
act to facilitate scientific research which would not otherwise take place. For example, the human presence on the Moon during the Apollo Project
resulted in the acquisition of scientific data which would not have been obtained otherwise, and the same is likely to hold
true for future human missions to both the Moon and Mars (and indeed elsewhere). In the more distant future, an important
scientific application of a well-developed human spaceflight infrastructure may be the construction of interstellar space
probes for the exploration of planets around other nearby stars.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献