The Midheaven, often abbreviated MC, is one of the principal angles of an astrological chart and is calculated from the specific time and location for which the chart is cast. In many common House systems, including Placidus, it forms the cusp of the Tenth House. Astrologers commonly associate the Midheaven with vocation, public identity, reputation, achievement, visibility, and the ways an individual may seek to contribute or establish a place in the wider world. Because its position depends strongly on time and location, an accurate birth time is important when determining the Midheaven in a natal chart. Its interpretation is usually considered together with its Zodiac Sign, ruling Planet, House relationships, Aspects, and the broader pattern of the chart.