Left: WISPR-O image of 26 January at 20:49 UT with the selected feature circled in red. Selecting this feature defines a line-of-sight from PSP to the feature. Right: simultaneous HI-1 image with points along the line sight from PSP to the selected feature for three distances along this line-of-sight, projected onto the image (red +’s). The points correspond to distances of 10, 27 and 44 R_⊙ ; the point corresponding to 27 R_⊙ falls on the feature selected in the WISPR-O image, which determines the feature’s coordinates (see text). The Sun (yellow globe) in the panel on the right is shown to scale. The HI-1 image is projected in the Helioprojective Cartesian (HPC) system (red and blue grid lines) with the Sun (yellow globe) drawn to scale.