Seismic observations shows that the inner core rotates faster than the mantle and the rotation axis of the inner core may not align with the rotation axis of the mantle. Free core nutation reflects co
This paper presents the past,present and future status of the Russian VLBI network "Quasar".This network has been developed for at least 20 years by the Institute of Applied Astronomy of the Russian A
The fast slewing rate and wide band of the VLBI2010 Global Observing System(VGOS) telescopes are beneficial to procure more observations and to obtain VLBI reference points(RPs) of high precisions.Mea