Term-day magnetic observations from the Prague-Clementinum observatory on 1848-12-21@en

Data of term-day observations recorded at the Prague-Clementinum observatory in years 1840-1849 are presented. The data were obtained by digitising and processing the original old records published in the yearbooks of this historical observatory. The term-day observations had been agreed for joint measurements by the observatories organised in the Göttingen Magnetic Union (GMU). Data of 120 term-days from January 1840 to December 1849 are published. The observations started at 10 p.m. of Göttingen Mean Time and lasted 24 hours. The interval between observations was 5 minutes (in April, June and July 1842 exceptionally 6 minutes). All time data were transformed into UT, based on the longitude of the Göttingen observatory, which was 9.950°. The time shift is thus 39'48''. The date in the term-day file name indicates the second day which involves substantial part of the observations (22 out of 24 hours).本数据集收录了1840年至1849年间布拉格克莱门特天文台（Prague-Clementinum observatory）记录的测时日（term-day）观测数据。该数据通过对该历史天文台年刊中刊载的原始老旧观测记录进行数字化处理后得到。测时日观测是由哥廷根磁学联合会（Göttingen Magnetic Union, GMU）组织旗下各天文台共同商定开展的联合测量项目。本次公开的数据集涵盖1840年1月至1849年12月间共计120个测时日的观测数据。观测以哥廷根标准时间当日22时启动，持续时长为24小时。观测间隔为5分钟；1842年4月、6月及7月的观测间隔例外设为6分钟。所有时间数据均基于哥廷根天文台的经度（9.950°）转换为世界时（UT），对应的时间偏移量为39分48秒。测时日数据文件的文件名所标注的日期，代表包含观测主体时段（24小时中的22小时）的第二日。