The parallax zero-point offset from <i>Gaia</i> EDR3 data

The second data release of \it Gaia \rm revealed a parallax zero point offset $-0.029$~mas based on quasars. value depended the position sky, and also likely magnitude colour. its dependence other parameters inhibited an improvement in local distance scale using e.g. Cepheid RR Lyrae period-luminosity relations. Analysis recent Early Data Release 3 (EDR3) reveals mean $-0.021$~mas team addresses detail proposes recipe to correct for it, ecliptic latitude, $G$-band magnitude, colour information. This paper is completely independent investigation into this issue focussing spatial correction quasars wide binaries. corrections are connected each overlap region between $17 < G 19$. presented at several resolutions HEALPix formalism. unclear any case secondary dependence. applied two samples brighter sources, namely sample $\sim$100 stars with trigonometric measurements from HST data, 75 classical cepheids photometric parallaxes. observed GEDR3 (excluding outliers) about $-39$~\muas, after applying it consistent being zero. For cepheid suggested that parallaxes may be underestimated by 5\%.