NTSC's activities on UT1 measurements and Earth Rotation Studies

• Autores: Wu, Y. W.; Yao, D.; Li, X. S.; Yang, H. Y.; Yang, X. H.; Zhang, S. G.
• Año de publicación: 2025
• Idioma: inglés
• Tipo de recurso: documento de conferencia
• Materia: Ciencias Astronómicas; Earth Orientation Parameters (EOP); Universal Time (UT1); Space geodetic techniques
• Institución: Universidad Nacional de La Plata

The Earth Orientation Parameters are a set of parameters that describe the Earth rotation’s statement and bridge the Celestial and Terrestrial Reference frame. EOP services are of importance for a wide range of applications in astronomy (astrometry and astronnomical instruments orientation), in geodesy (Positioning and navigation on the Earth’s surface and in space), and in operation of deep space missions (Lunar and Mars explorations). 3 out of 5 EOP parameters, including the Universal Time (UT1) and the Celestial Pole Offsets (dX, dY), can only be determined by very long baseline interferometry (VLBI) observations. The Length of Day variations (ALOD) and Polar motions (PMX, PMY) can also be determined by other 3 space geodetic techniques, including the satellite laser ranging (SLR), the Global Navigation Satellite System (GNSS), and the Doppler orbitorgraphy and radiopositioning integrated by satellite (DORIS), all of which use artificial satellites as target. In the aim to keep the Earth Rotation time scale UT1, recently, the national time service center of Chinese Academy of Sciences built a team dedicated for UT1 measurements and services [3]. Currently, we operate a domestic VLBI network [1], data center and analysis center of the international GNSS Monitoring and Assessment System (iGMAS), and 3 SLR. stations. Studies on software development, EOP combinations [4], EOP predictions [2] and Earth Rotation variation theory are also in progress. Here we report our recent activities on UT1 measurements and Earth rotation studies.
Facultad de Ciencias Astronómicas y Geofísicas