Variation in the position angle (top panel) and the orbital separation (r/a) as a function of the orbital phase computed according to the orbital solution from Blomme et al. (2024). The position angle is measured in the orbital plane and is defined here as the angle between the line joining the two stars and the direction of conjunction with the primary star (labelled component A in Blomme et al. 2024) in front. Phase 0.0 corresponds to periastron passage. Bottom panel: X-ray flux of HD 168112 in the 0.5–10 ke V energy band corrected for absorption by the ISM as a function of orbital phase along with the best fit 1/r scaling of the colliding wind X-ray emission given by Eq. (3).