IERS数据动态提取与更新系统的设计与实现

Design and Implementation of a Dynamic System of Retrieving and Updating IERS Data

在高精度的位置计算中需要获取计算时刻所在日期的闰秒,以及UT1-UTC等关键数据,但长期以来这一类数据的维护均是手工进行,出错率高。针对新一代中国太阳射电日像仪观测与数据处理过程中的位置计算需要,实现了一个自动提取国际地球自转服务(IERS)参数的数据更新自维护子系统。系统可以根据需要自动运行、自动下载并分拆IERS网站数据,采用正则表达式从文本中自动获取所需要的实测值与预报值,自动在本地构建一个2004年12月31日以来的IERS数据库,并根据每周所获得的数据维护整个IERS的数据,将最新的实测值与预报值存入数据文件,实现了数据的滚动更新。系统彻底解决了手工维护数据的问题,为中国太阳射电日像仪的自动数据处理流水线打下了较好的基础。同时,本文提出的方法是一种通用的方法,可以方便地集成应用到国内其它天文位置计算领域。

It is a fundamental issue in astronomical research to achieve high-precision calculations of target positions. To fulfill the requirements of high-precision calculations of positions in pipeline data processing for the Chinese Solar Radio Heliograph （ CSRH）, in this paper we propose a dynamic system of automatically retrieving and updating data to obtain useful parameter values from the IERS website. The method can automatically download and analyze a text file published on the IERS website. Values of the needed parameters, including the earth orientation, leap second, and polar motion, can be extracted from canonical expressions of the text file and saved to a specified local file. The values include measured and predicted ones. With the method a local database of IERS parameter records since December 31, 2004 has been established. The database is being updated weekly in the automated mode by checking the IERS website. Our study provides a general method to maintain astronomical data essential to high-precision calculations of target positions. It avoids the conventional need to manually maintain such data. It is valuable to the design of pipeline data processing for the CSRH. The routines for the method were written with the Python language and can be easily integrated into other astronomical software packages.