Space Pnysics Developed by High-Precise Astrometry

依巴谷卫星为我们带来了一个利用恒星的三角视差π进行测距的新纪元。在希巴谷之前，地面观测只提供几十个pC以内的恒星的π，而我们已经到了获取距离延伸到-1-2kpc的恒星的π的阶段。因此，依巴谷星表包含了许多有价值的恒星，其中包括作为主要距离指示器的造父变星和天琴座RR恒星。众所周知，造父变星遵循周期-光度(PL)关系。PL的零点给出了到大麦哲伦云(LMC)的距离模数MLMC，这无疑是确定到遥远星系的距离的重要一步，从而也是确定泡泡常数(H0)的重要一步。以同样的方式，遵循金属光度(ML)关系的RR星系也提供了LMC--此外，它们确实被用来确定到银河系球状星团的距离，从而确定它们的年龄。…到目前为止，依巴谷没有间接校准这些零点，而是使我们能够第一次从银河系造父变星和天琴座RR的π中直接得出这些零点。然而，事实上，直接校准面临着一个严重的问题，这是因为几乎所有这些变量的π都是在测量包括负视差在内的非常大的误差的情况下产生的。在这种情况下，不能从d(PC)=I/π计算每个变量的距离d。因此，我们需要从依巴谷视差系综中统计地推导出物理量。在这项研究中，我们调查了两种统计方法对校正依巴谷视差的严格程度。所有讨论都将以依巴谷变量给出的JILMC和解协议告终。通过统计校准精确确定最终结果中所涉及的偏差和方差，这不仅是使用希帕科斯数据进行进一步研究的需要，也是利用正在进行的空间卫星项目如DIVA和FAME带来的高精度天文测量数据开展的未来工作所必需的。较少

The Hipparcos satellite have brought us a new era for the distance determination using the trigonometric parallaxes π of stars. Before Hipparcos, the ground-based observations offered π only for stars within a few tens pc, - and we are already at the stage to obtain π for stars with their distances extending to -1-2 kpc. As a result, the Hipparcos catalog invloves many valuable stars, of which Cepheid variables and RR Lyrae stars which serve as primary distance indicators are included. It is well-known that Cepheids obey the period-luminosity (PL) relation. The zero-point for PL gives a distance modulus MLMC to the Large Magellanic Cloud (LMC), which is no doubt an important step for determining the distances to distant galaxies and thus for the Bubble constant (H0). In the same manner, the RR ALyraes which obey the metallicty-luminosity (ML) relation also provide ^LMC- In addition, they are indeed used to determine the distances to the Galactic globular clusters and hence their ages. … More Instead of the indirect calibrations of these zero-points so far, Hipparcos has enabled us to derive them directly from π of Galactic Cepheids and RR Lyraes for the first time. However, in fact, direct calibrations have confronted a serious problem which comes from the fact that almost all of π for these variables are measured with very large error including negative parallaxes. In such a case, the distance d for each variable cannot be calculated from d(pc) = I/π. We therefore need do deduce the physical quantities statistically from the ensemble of Hipparcos parallaxes. In this research, we investigate how rigorous two statistical methods are to calibrate Hipparcos parallaxes. All discussions will end in the settlement of JILMC given by Hipparcos variables. The precise determination of biases and variances involved in the final results by the statistical calibrations is certainly required for not only the further study using Hipparcos data but also the future work using the highly-precise astrometric data brought by the ongoing space satellite projects such as DIVA and FAME. Less