Ecliptic Longitude is a coordinate used in astronomy to specify the position of an object in the sky relative to the Earth and the Sun. It measures the angle along the ecliptic plane, which is the apparent path of the Sun across the sky throughout the year. The angle is measured in degrees, starting from the point of the vernal equinox. This system helps astronomers track celestial bodies, such as planets and stars, as they move along their orbits. Ecliptic longitude is essential for understanding the positions of these objects in relation to each other and for predicting their future locations in the sky.