Chart Elements: Parts of the Astrological Birth Chart Along with planets, every chart has pieces and sections, like an astrological pie. The chart is a 360-degree circle. Every chart has a horizon line that runs from the Ascendant at the left (Eastern horizon) across to the Descendent. And then there's another line, the meridian that runs from the top of the chart (the Midheaven) to the bottom (the IC or Imedium Coeli).