空间参考架与地面参考架的比较  

Proper-motion Comparison of Space-based System with Ground-based System

作　　者：朱紫[1] 

机构地区：[1]中国科学院陕西天文台 临潼 710600

出　　处：《科学技术与工程》2002年第4期19-22,共4页Science Technology and Engineering

基　　金：国家自然科学基金(10073014)

摘　　要：深入分析了地面FK5与空间Hipparcos自行系统之间的关系。研究发现,基于FK5的PPM和ACRS两自行系统均存在局域差、星等差和色差,且对这两个系统而言,各项误差都具有类似的表现。同时发现,FK5与Hipparcos自行系统之间的旋转关系无法用VLBI和LLR所测定的岁差常数改正来解释。SPM Catalog 2.0地面系统给出了直接相对于河外源的绝对自行观测。通过比较SPM Catalog 2.0与Hipparcos自行系统,发现两旋转分量ω_x和ω_z明显小于Hipparcos系统的惯性误差±0.25mas·a^(-1),而另一分量ω_x则几乎是这一误差量的两倍。An intensive analysis of the ground-based FK5 propermotion system with the space-based Hipparcos proper motions is presented. Region-, magnitude-, and color-dependent systematic errors in the PPM and ACRS proper motions are found and exhibit similar tendencies for both catalogs. The term of the global rotation between the FK5 and Hipparcos proper-motion systems cannot be explained by the constant of the FK5 precessional correction, which is given by the VLBI and LLR observations. Comparing the Hipparcos proper motions with those of the ground based SPM Catalog 2.0, which provides absolute proper motions of objects measured directly relative to external galaxies, it is found that tbe two components of the spin vector, ω_x and ω_z, are apparently less than the value of 0.25 mas·a^(-1) for the uncertainty of the Hipparcos inertiality, while the component ω_v is almost twice that value.

关 键 词：空间参考架 地面参考架 比较 天体测量 参考系 星表 自行 

分 类 号：P124[天文地球—天体测量]