Axes stability of the ICRF3 from VLBI position time series (Liu et al. 2022, A&A 659, A75)Abstract
Using very long baseline interferometry (VLBI) observations spanning 1979–2020, we evaluated the axis stability of the third realization of the International Celestial Reference Frame (ICRF3). Extragalactic source position time series were derived and analyzed to determine the global spin and yearly orientation of the frame axes. The global spin is less than 0.8 μas yr⁻¹ per axis, corresponding to an accumulated deformation under 30 μas. The dispersion of yearly frame orientations is typically 10–20 μas, confirming that the ICRF3 axes remain stable since its adoption.
The celestial reference frame provides the fundamental position reference for astronomy and geodesy.
Using VLBI dual S/X-band observations from August 1979 to December 2020, Liu et al. (2022) derived
time series of 5290 extragalact