Timelapse footage of the shadow of a monument built to mark the Earth's equator, filmed on an equinox. This monument is on the island of Ilheu das Rolas, Sao Tome and Principe. The metal bar set in the world map mosaic marks the position of the equator. This monument, called The Mark of the Equator, is located just 6.5 degrees east of the point where the equator and Prime Meridian meet. On the equinoxes, the shadow of this monument moves west to east along the equator line, as the Sun passes directly overhead. This sequence was filmed on the March equinox, 2017.