The Midheaven is the angle at the cusp of the 10th house, located at the top of your natal chart and representing your public face.
The Midheaven – just like the Ascendant – is not a planet but a mathematical point in your birth-chart. Another name for the Midheaven is MC or Medium Coeli, meaning “middle of the heavens”. As the word suggests, the Midheaven is the highest point in the sky along the ecliptic – the point where the apparent path of the sun crosses the meridian at the precise location of our birth.