Changes in the shape of earths orbit around the sun can take how long?

Changes in the shape of Earth's orbit around the Sun, known as orbital eccentricity, occur over a cycle of about 100,000 years. This variation is part of the Milankovitch cycles, which describe how Earth's orbital parameters change due to gravitational interactions with other celestial bodies. These long-term changes influence climate patterns, including glacial and interglacial periods.