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Astronomers are entering an era of {\mu}as-level astrometry utilizing the5-decade-old IAU Galactic coordinate system that was only originally defined to$\sim$0{\deg}.1 accuracy, and where the dynamical centre of the Galaxy (Sgr A*)is located $\sim$0{\deg}.07 from the origin. We calculate new independentestimates of the North Galactic Pole (NGP) using recent catalogues of Galacticdisc tracer objects such as embedded and open clusters, infrared bubbles, darkclouds, and young massive stars. Using these catalogues, we provide two newestimates of the NGP. Solution 1 is an "unconstrained" NGP determined by thegalactic tracer sources, which does not take into account the location of SgrA*, and which lies 90{\deg}.120$\,\pm\,$0{\deg}.029 from Sgr A*, and Solution 2is a "constrained" NGP which lies exactly 90{\deg} from Sgr A*. The"unconstrained" NGP has ICRS position: $\alpha_{NGP}$ = 192{\deg}.729 $\,\pm\,$0{\deg}.035, $\delta_{NGP}$ = 27{\deg}.084 $\,\pm\,$ 0{\deg}.023 and $\theta\,$= 122{\deg}.928 $\,\pm\,$ 0{\deg}.016. The "constrained" NGP which lies exactly90{\deg} away from Sgr A* has ICRS position: $\alpha_{NGP}$ = 192{\deg}.728$\,\pm\,$0{\deg}.010, $\delta_{NGP}$ = 26{\deg}.863 $\,\pm\,$ 0{\deg}.019 and$\theta\,$ = 122{\deg}.928 $\,\pm\,$ 0{\deg}.016. The difference between thesolutions is likely due to the Sun lying above the Galactic midplane.Considering the angular separation between Sgr A* and our unconstrained NGP,and if one adopts the recent estimate of the Galactocentric distance for theSun of $R_{0}$ = 8.2$\,\pm\,$0.1 kpc, then we estimate that the Sun lies$z_{\odot}$ $\simeq$ 17$\,\pm\,$5 pc above the Galactic midplane. Our value of$z_{\odot}$ is consistent with the true median of 55 previous estimatespublished over the past century of the Sun's height above the Galacticmid-plane ($z_{\odot}$ $\simeq$ 17$\,\pm\,$2 pc).

Revised Geometric Estimates of the North Galactic Pole and the Sun's Height Above the Galactic Midplane