Fig. 3

Left plot a Time series of UT1-UTC for December 2019 through February 2020. Shown are IERS Bulletin B values (grey stars) and the VGOS-B results as (red circles). The light blue symbols show the INT1/INT2 results of BKG (squares), GSF (upward-pointing triangles), USN (downward-pointing triangles), GSI (left-pointing triangles), and IAA (right-pointing triangles). The INT1/INT2 results from OSO are shown as light-red diamonds. To increase readability, all series, except the VGOS-B one, are offset by \(-3\) ms each from the series shown directly above. Right plot b Differences with respect to IERS Bulletin B values for simultaneously observed INT1 and VGOS-B sessions