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1.
P. K. Seidelmann 《Celestial Mechanics and Dynamical Astronomy》1982,27(1):79-106
In 1979 the Seventeenth General Assembly of the International Astronomical Union (IAU) in Montreal, Canada, adopted the 1979 IAU Theory of Nutation upon the recommendation of this Working Group. Subsequently the International Union of Geodesy and Geophysics (IUGG) passed a resolution requesting that this action be reconsidered in favor of a theory based on a different Earth model. As a consequence of that reconsideration the 1980 IAU Theory of Nutation was adopted. The details of that theory and the history of its adoption are described here in the Final Report of the IAU Working Group on Nutation. A summary of these events and the essence of our recommendations is provided first while the body of the report discusses these matters in greater detail. The theory itself is contained in Table I. 相似文献
2.
Peter Jenniskens 《Earth, Moon, and Planets》2008,102(1-4):5-9
The International Astronomical Union at its 2006 General Assembly in Prague has adopted a set of rules for meteor shower nomenclature,
a working list with designated names (with IAU numbers and three-letter codes), and established a Task Group for Meteor Shower Nomenclature in Commission 22 (Meteors and Interplanetary Dust) to help define which meteor showers exist from well defined groups of
meteoroids from a single parent body. 相似文献
3.
IAU 1976天文常数系统中的基础常数 总被引：2，自引：2，他引：0
对ＩＡＵ１９７６天文常数系统中的基础常数的测定方法进行了评述,指出十个基础常数已发生了许多变化,光速已成为常数,地球赤道半径可用于大地水准面的重力势代替,黄经总岁差需进行修改,章动常数已不能称为基础常数,其它常数也都有了新的测定结果,ＩＡＵ１９７６天文常数系统已跟上不天文学的发展,并存在很大的缺陷,必须进行修订和改进,天文常数的测定方法和理论研究都在迅速发展之中,我们应当关心这个领域的研究。 相似文献
4.
回顾了1900年以来LAU采用天文常数系统的简况,以及一些天文常数之间的数学关系,并描述了以前每次改变天文常数系统的主要因为.介绍了1991年以来IAU在天文常数方面的工作:包括IAU天文常数工作组和天文常数最佳估计值的情况.叙述了IAU 2009年天文常数系统替代IAU 1976天文常数系统的因为:随着人类对太阳系的探测,获得新的天文常数测定值;1991年以来在相对论框架下BCRS和GCRS的使用;P03岁差模型和MHB2000章动模型的采用.比较了IAU2009和1976天文常数系统的差异.最后介绍中国在天文常数方面工作的情况和今后工作的建议. 相似文献
5.
The IAU Meteor Data Center in Lund has acted as a central depository for meteor orbits obtained by photographic, video and
radar techniques. The database of precisely reduced photographic meteors contains data on 4581 meteor orbits obtained by 17
different stations or groups in the period 1936–1996. The orbital and geophysical data are available in two separate files
as well as in an alternative file with the merged data. In various studies of meteoroid streams as well as in studies of the
sporadic meteor background, it is often necessary to utilize both the orbital and the geophysical data files. Since the database
is a compilation of partial, not perfectly compatible catalogues from many observing stations, the merging of parameters from
one data set to another may sometimes present problems. The present contribution is a note on some problems encountered in
the merging procedure. Moreover, it is evident that the database includes a small amount of erroneous data – either in the
observations or in the subsequent data reductions. The latter error is not surprising in view of the lack of modern computers
at several stations in the past. A final, corrected version of the IAU MDC Lund photographic meteor orbits (eq. 2000.0) can
now be requested through the homepage of the Astronomical Institute, Slovak Academy of Sciences (http://www.astro.sk/~ne/IAUMDC/Ph2003/database.html). 相似文献
6.
简要地回顾和介绍了IAU时间尺度和参考系的历史和进展，其主要内容：（1）牛顿时空观和相对论时空观，（2）IAU各种时间尺度的历史演变和相互关系；（3）IAU的天文参考系，有关的最新决议,相对论框架下度规及其规范问题，四维时空中的空间1PN坐标变换，也介绍了一些有关工作，阐明了与IAU最新决议稍有不同的观点，指出目前IAU有关决议可能仍存在的某种程度上的不完善。 相似文献
7.
Since 1984, the new IAU (1976) System of Astronomical Constants has become effective; meanwhile, the new lunar and planetary ephemerides (DE200/LE200) have been introduced into the Astronomical Almanac. In order to obtain the best fit of these ephemerides to the observational data, some modifications to the constants were made (Kaplan 1961). The modified values of these constants have been accepted by many users (particularly in the Merit Project), (Melbourne et al. 1983), although there has not been any new resolution of IAU. To avoid these inconsistencies, it seems to be necessary to rediscuss the adopted value of some astronomical constants in the new system. This paper discusses the problems for selection of the precession quantities and derives the precession expressions based on the motion of ecliptic from the DE ephemeris. 相似文献
8.
Precise astrometric observations show that significant systematic differences of the order of 10 milliarcseconds (mas) exist between the observed position of the celestial pole in the International Celestial Reference Frame (ICRF) and the position determined using the International Astronomical Union (IAU) 1976 Precession (Lieske et al., 1977) and the IAU 1980 Nutation Theory (Seidelmann, 1982). The International Earth Rotation Service routinely publishes these 'celestial pole offsets', and the IERS Conventions (McCarthy, 1996) recommends a procedure to account for these errors. The IAU, at its General Assembly in 2000, adopted a new precession/nutation model (Mathews et al., 2002). This model, designated IAU2000A, which includes nearly 1400 terms, provides the direction of the celestial pole in the ICRF with an accuracy of ±0.1 mas. Users requiring accuracy no better than 1 mas, however, may not require the full model, particularly if computational time or storage are issues. Consequently, the IAU also adopted an abridged procedure designated IAU2000B to model the celestial pole motion with an accuracy that does not result in a difference greater than 1 mas with respect to that of the IAU2000A model. That IAU2000B model, presented here, is shown to have the required accuracy for a period of more than 50 years from 1995 to 2050. 相似文献
9.
The IAU Symposium S202 of the 24th General Assembly (Manchester, August 7–18, 2000) was dedicated to new, rapidly developing areas of stellar–planetary astronomy—extrasolar planet discoveries, dust rings, the theory of the formation and evolution of orbits, and future research perspectives. A short review of the symposium is presented. 相似文献
10.
J. H. Lieske 《Celestial Mechanics and Dynamical Astronomy》1993,57(3):473-491
In 1970 the IAU defined any object'snorth pole to be that axis of rotation which lies north of the solar system's invariable plane. A competing definition in widespread use at some institutions followed the right hand rule whereby the north axis of rotation was generally said to be that that of the rotational angular momentum. In the case of the latter definition, the planet Neptune and its satellite Triton would have their north poles in opposite hemispheres because Triton's angular momentum vector is in the hemisphere opposite from that of Neptune's rotation angular momentum.The IAU resolutions have been somewhat controversial in some quarters ever since their adoption. A Working Group has periodically updated the recommended values of planet and satellite poles and rotation rates in accordance with the IAU definition of north and the IAU definition of prime meridian. Neither system is completely satisfactory in the perception of all scientists, and some confusion has been generated by publishing data in the two different systems.In this paper we review the IAU definitions ofnorth and of the location ofprime meridian and we present the algorithm which has been employed in determining the rotational parameters of the natural satellites. The IAU definition of the prime meridian contains some ambiguities which in practice have been specified by the numerical values published by the IAU working group but which have not yet been explicitly documented. The purpose of this paper is to explicitly document the algorithm employed by the IAU working group in specifying satellite poles and rotation rates. 相似文献
11.
12.
A new 2013 version of the IAU MDC photographic meteor orbits database which is an upgrade of the current 2003 version (Lindblad et al. 2003, EMP 93:249–260) is presented. To the 2003 version additional 292 orbits are added, thus the new version of the database consists of 4,873 meteors with their geophysical and orbital parameters compiled in 41 catalogues. For storing the data, a new format enabling a more simple treatment with the parameters, including the errors of their determination is applied. The data can be downloaded from the IAU MDC web site: http://www.astro.sk/IAUMDC/Ph2013/ 相似文献
13.
Report of the IAU Working Group on Cartographic Coordinates and Rotational Elements: 2009 总被引：5，自引：0，他引：5
B. A. Archinal M. F. A��Hearn E. Bowell A. Conrad G. J. Consolmagno R. Courtin T. Fukushima D. Hestroffer J. L. Hilton G. A. Krasinsky G. Neumann J. Oberst P. K. Seidelmann P. Stooke D. J. Tholen P. C. Thomas I. P. Williams 《Celestial Mechanics and Dynamical Astronomy》2011,109(2):101-135
Every three years the IAU Working Group on Cartographic Coordinates and Rotational Elements revises tables giving the directions of the poles of rotation and the prime meridians of the planets, satellites, minor planets, and comets. This report takes into account the IAU Working Group for Planetary System Nomenclature (WGPSN) and the IAU Committee on Small Body Nomenclature (CSBN) definition of dwarf planets, introduces improved values for the pole and rotation rate of Mercury, returns the rotation rate of Jupiter to a previous value, introduces improved values for the rotation of five satellites of Saturn, and adds the equatorial radius of the Sun for comparison. It also adds or updates size and shape information for the Earth, Mars?? satellites Deimos and Phobos, the four Galilean satellites of Jupiter, and 22 satellites of Saturn. Pole, rotation, and size information has been added for the asteroids (21) Lutetia, (511) Davida, and (2867) ?teins. Pole and rotation information has been added for (2) Pallas and (21) Lutetia. Pole and rotation and mean radius information has been added for (1) Ceres. Pole information has been updated for (4) Vesta. The high precision realization for the pole and rotation rate of the Moon is updated. Alternative orientation models for Mars, Jupiter, and Saturn are noted. The Working Group also reaffirms that once an observable feature at a defined longitude is chosen, a longitude definition origin should not change except under unusual circumstances. It is also noted that alternative coordinate systems may exist for various (e.g. dynamical) purposes, but specific cartographic coordinate system information continues to be recommended for each body. The Working Group elaborates on its purpose, and also announces its plans to occasionally provide limited updates to its recommendations via its website, in order to address community needs for some updates more often than every 3 years. Brief recommendations are also made to the general planetary community regarding the need for controlled products, and improved or consensus rotation models for Mars, Jupiter, and Saturn. 相似文献
14.
Toshio Fukushima Masa-Katsu Fujimoto Hiroshi Kinoshita Shinko Aoki 《Celestial Mechanics and Dynamical Astronomy》1986,38(3):215-230
The relation between the units and readings of time and space coordinates of terrestrial and barycentric reference frames is discussed from the viewpoint of general relativity. Attention is paid to the unit of space coordinates since the International Astronomical Union (IAU) regulates only the unit of time in the above two frames. Two definitions of unit of length are examined and their effects on the numerical expression of coordinate transformation, equations of planetary motions, and those for light propagation time are discussed. A clear conflict is found between the IAU (1976) recommendation on the definition of the time-scales in different frames of reference and the statement that all constants in the IAU (1976) new system of astronomical constants are defined in terms of the Internationsl System of units (SI units). One of the above two definitions is proposed to resolve this conflict by the least alteration to current procedures for analysing the recent astrometric observations such as the radar/laser rangings, the range and range-rate, and the very long baseline interferometric observations. Also, an interpretation of numerical values in the IAU (1976) new system of astronomical constants is presented. It is stressed that the definition proposed in this paper requires that a formula slightly different from that in current use be employed in the numerical transformation of readings of coordinates between the terrestrial and barycentric reference frames. 相似文献
15.
G. Chiumiento M. G. Lattanzi G. Massone R. Morbidelli R. Pannunzio M. Sarasso 《Astrophysics and Space Science》1991,177(1-2):93-96
We present optical positions in the improved IAU System at the standard epoch J2000.0 of some extragalactic radio sources obtained at Torino Astronomical Observatory. The primary reference stars are taken from the Carlsberg Automatic Meridian Catalogues 1 and 2 (CAMC). 相似文献
16.
David Morrison 《Icarus》1976,28(4):605-606
The proposed new International Astronomical Union nomenclature for topographic features on Mercury, as uncovered by Mariner 10, is briefly outlined. 相似文献
17.
Jean Kovalevsky 《Celestial Mechanics and Dynamical Astronomy》1971,4(2):213-223
Sans résumé
Presented at IAU Colloquium No. 9, The IAU System of Astronomical Constants', Heidelberg, Germany, August 12–14, 1970. 相似文献
Presented at IAU Colloquium No. 9, The IAU System of Astronomical Constants', Heidelberg, Germany, August 12–14, 1970. 相似文献
18.
H. Scholl 《Celestial Mechanics and Dynamical Astronomy》1971,4(2):250-252
An analysis of the observations of the minor planets (153) Hilda, (279) Thule and (334) Chicago yields the following values for the reciprocal mass of Jupiter: (153) Hilda 1047.378±0.019, (279) Thule 1047.347±0.023, (334) Chicago 1047.325±0.010. A possible error in the mass of Saturn that might affect these results is discussed.Presented at IAU Colloquium No. 9, The IAU System of Astronomical Constants, Heidelberg, Germany, August 12–14, 1970. 相似文献
19.
W. J. Klepczynski P. K. Seidelmann R. L. Duncombe 《Celestial Mechanics and Dynamical Astronomy》1971,4(2):253-272
A set of masses for the principal planets is derived systematically from all available fundamental and independent determinations. In deriving these values an attempt has been made to treat independently those determinations based on differing observational types or analytical methods.Presented at IAU Colloquium No. 9, The IAU System of Astronomical Constants, Heidelberg, Germany, August 12–14, 1970. 相似文献
20.
A. Bec 《Celestial Mechanics and Dynamical Astronomy》1971,4(2):277-278
Sans résuméPresented at IAU Colloquium No. 9, The IAU System of Astronomical Constants, Heidelberg, Germany, August 12–14, 1970. 相似文献