argument of perihelion âruzmân-e pirâhur Fr.: argument du périhélie The angular distance between the → ascending node of an object orbiting the Sun and its perihelion. Argument of perihelion is measured in the → orbital plane with respect to the Sun and in the direction of motion. It is one of the → orbital elements and usually shown with the symbol ω. See also: → argument of perigee, → argument of periapsis. → argument; → perihelion. |