Their curved form, orientation and azimuth position takes inspiration from the transitory and natural arc of the sun’s journey, the diurnal cycle of seasons in Melbourne and the Hassall Sun Chart. The tip of the pillars is slightly angled as they follow the respective peak altitude of the sun, at 1pm (refer to Sun's Diurnal Cycle page).
From the beginning of October to April, there is a sudden difference of the height of the celestial movement due to what we call daylight savings as the sun takes longer time to set and from April to oct the sun sets faster as it is demonstrated on the sun graph that I made, taller in the beginning of the year and shortens mid-year as it reverses towards the end.