This document proposes replacing Mao Zedong's portrait above Tiananmen Gate in Beijing with a new astronomical clock called the "24 Hour Geographical Galactic Clock". The clock would show the position of the sun, Milky Way galaxy, and solar system over time. It would represent the period from the birth of the sun 4.6 billion years ago until the end of life on Earth in about 5 billion more years, compressed into 24 hours. The clock's design aims to link Earth time to the sun's long-term movement around the galactic center and show where the solar system will be at key biological moments.