Zoom onto the observation shown in Fig. 2. The red line is the observation found by Perlbarg et al. (2023). The observation has the appearance of a line, because the photographic plate has an exposure time of 50 min. The blue dots and thin blue ellipsoids around them predict the beginning of the actual observation. The green thin part of the ellipsoid is as before the uncertainty region of the nominal position constructed from only the covariance matrix. The light-blue lines starting from the blue dots predict the direction and the length of the actual observation.