Open AccessThe Optical Measuring System of Universal Time: Digital Zenith Tube
Author(s) -
Haiwen Cai,
Jianpeng Xu,
Shaojie Chen
Publication year - 2021
Publication title -
journal of physics. conference series
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.21
H-Index - 85
eISSN - 1742-6596
pISSN - 1742-6588
DOI - 10.1088/1742-6596/1739/1/012015
Subject(s) - zenith , universal time , geodesy , earth's rotation , measure (data warehouse) , remote sensing , reference frame , tube (container) , orientation (vector space) , rotation (mathematics) , total station , frame (networking) , computer science , optics , physics , geology , mathematics , engineering , mechanical engineering , telecommunications , geometry , computer vision , astronomy , database
Universal Time is one of the Earth Orientation Parameters, which reflects the Earth’s rotation. Universal Time is the necessary parameter to build up the connection between the celestial reference frame and the terrestrial reference frame. In present, to measure Universal time relies mainly on Very Long Baseline Interferometry technique, but the period of gaining the observing result is a few weeks later although its measuring accuracy is very high. For shortening the data period and cutting the cost of observations, National Time Service Center constructed the Digital Zenith Tube net. In this paper, we state the structure of Digital Zenith Tube, its observation principle, observing features, observing process, and the system composing of the observing net. The Digital Zenith Tube net can also measure the deflections of the vertical of local stations which is an important parameter in the geodesy.