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 共查询到13条相似文献,搜索用时 62 毫秒
1.
国际地球参考框架:现状与未来   总被引:6,自引:0,他引:6  
地球参考框架是研究地球整体和局部运动以及探讨地球各圈层运动机制的一个重要基准。简要回顾地球参考架的发展和现状,主要分析当前取得的成绩及其存在问题和局限性,着重提出未来地球参考架的目标和若干建议。  相似文献   

2.
ITRF2005简介和评析   总被引:5,自引:0,他引:5  
该文对最新的国际地球参考框架 ITRF2005进行了简单介绍,指出了IFRF2000与ITRF2005之间在解的生成,基准的定义和实现等方面的差别,特别评析了ITRF2005所作改进的理由和合理性.同时也指出了ITRF2005与ITRF2000一样,没有满足协议地球参考系(CTRS)的定向随时间的演化需遵循相对于地壳无整体旋转(NNR)的约束条件,并就此提出了解决办法.  相似文献   

3.
基于ITRF2000的全球板块运动模型   总被引:3,自引:0,他引:3  
  相似文献   

4.
建立了 3种板块的绝对运动模型。即假定太平洋海岭相对固定于下地幔而得到的PRF -ITRF2 0 0 0的板块绝对运动模型 ;根据热点资料推得的HS2 -ITRF2 0 0 0板块绝对运动模型和由ITRF2 0 0 0得到的NNR -ITRF2 0 0 0无整体旋转的板块绝对运动模型。比较了这 3种板块绝对运动模型的利弊。综合起来看PRF -ITRF2 0 0 0可能是一个比较合适的基于空间数据的绝对参考架  相似文献   

5.
通过比较地球定向参数(EOP)序列和对应的地固参考架,本文得到了依巴谷输入星表(HIC)和国际地球自转服务(IERS)基于甚长基线干涉测量(VLBI)建立的河外天球参考架(ICRF)之间的旋转参数,在J2000.0历元,前者至后者的旋转参数为[8.4±1.1mas,46.7±1.1mas,45.5±1.5mas],其时间变率为[-0.14±0.05mas/a,3.22±0.05mas/a,5.70±0.07mas/a]。依巴谷输入星表是完全基于FK5系统的,本文得到的旋转参数与ICRF和FK5之间的系统差异情况相符  相似文献   

6.
A relation between the Celestial Reference System (CRS) and the Terrestrial Reference System is established theoretically by solving the equations of motion of a rigid Earth under the influence of the Sun and the Moon up to the second order perturbation. The solutions include not only nutation including Oppolzer terms but also the right ascension of the dynamical departure point (DP), as well as the wobble matrix.We have found that the kinematical definition of the Non-Rotating Origin NRO (for which our term is DP) given by Capitaine, Guinot and Souchay (1987) is not entirely equivalent to that included in the solutions of the equations of motion but shows perturbation, in particular when this is taken on the instantaneous equator. Besides this serious fault, we feel little merit in taking the DP as reference: (1) Unnecessary spurious mixed secular terms appear which come from the geometrical configuration that the DP leaves far and far from the ecliptic. (2) the DP moves secularly as well as oscillating with respect to space; this literally contradicts the term NRO, or is at least misleading. (3) It does not free us from the precession uncertainty to adopt DP as reference, since we cannot avoid virtual proper motions in terms of the current CRS. (4) No terms ignored hitherto are introduced, even if we take the DP properly chosen, i.e., on the equator of the celestial ephemeris pole. The transformation is only mathematical. There is no sufficient reason to take it instead of the equinox, which is observable in principle, as reference at the cost of the labor of changing all the textbooks, ephemerides, data and computer software now existing.  相似文献   

7.
8.
通过比较地球定向参数(EOP)序列和对应的地因参考架,得到了依巴谷输入星表(HIC)和临时星表H37与国际地球自转服务(IERS)基于甚长基线干涉测量(VLBI)建立的河外天球参考架(ICRF)之间的旋转参数。在J2000.0历元,HIC和H37至ICRF的旋转分别为[7.4±1.1mas,70.0±1.2mas,86.8±6.9mas]和[-27.4±1.0mas,10.4±1.0mas,70.3±4.6mas]。由于光学仪器位置坐标精度较低,第三个旋转角的可信度较差。  相似文献   

9.
国际地球自转服务(IERS)评介   总被引:2,自引:0,他引:2  
回顾了建立国际地球自转服务(IERS)的历史过程,简述了IERS机构各部门的设置及其作用。着重介绍了IERS重建的理由和过程以及新IERS机构的组成。最后给出IERS成果对现有科学研究的作用和意义。  相似文献   

10.
朱紫 《天文学进展》2001,19(2):302-306
通过分析和比较依巴谷自行系统与FK2.0自行系统之间的关系,研究了依巴谷系统的惯性问题,指出该系统可能然存在较大的非惯性剩余旋转。  相似文献   

11.
A system of averaged equations of planetary motion around a central star is constructed. An astrocentric coordinate system is used. The two-planet problem is considered, but all constructions are easily generalized to an arbitrary number N of planets. The motion is investigated in modified (complex) Poincarécanonical elements. The averaging is performed by the Hori–Deprit method over the fast mean longitudes to the second order relative to the planetary masses. An expansion of the disturbing function is constructed using the Laplace coefficients. Some terms of the expansion of the disturbing function and the first terms of the expansion of the averaged Hamiltonian are given. The results of this paper can be used to investigate the evolution of orbits with moderate eccentricities and inclinations in various planetary systems.  相似文献   

12.
本文叙述了测定天球参考架零点位置的意义和途径,通过比较,认为小行星是最合适的观测对象,并且在分析了过去用小行星观测测定天球参考架零点位置的误差较大的原因后,提出了用低纬子午环高精度地测定小行星瞬时位置的观测方法。  相似文献   

13.
Regular measurements of the general magnetic field of the Sun, performed over about half a century at the Crimean Astrophysical Observatory, the J. Wilcox Solar Observatory, and five other observatories, are considered in detail for the time 1968?–?2016. They include more than twenty-six thousand daily values of the mean line-of-sight field strength of the visible solar hemisphere. On the basis of these values, the equatorial rotation period of the Sun is found to be 26.926(9) d (synodic). It is shown that its half-value coincides within error limits with both the main period of the magnetic four-sector structure, 13.4577(25) d, and the best-commensurate period of the slow motions of the major solar system bodies, 13.479(22) d (sidereal). The probability that the two periods coincide by chance is estimated to be about \(10^{-7}\). The true origin of this odd resonance is unknown.  相似文献   

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