Our planet does not experience an ice age every 100,000 years. Ice ages occur much less frequently and last for much longer periods. The last ice age, known as the Pleistocene Ice Age, began 2.6 million years ago and several major glacial periods have occurred during that time. The most recent glacial period ended about 10,000 years ago, and we are currently in an interglacial period. Ice ages are caused by a combination of factors, including changes in the Earth's orbit around the sun, changes in the tilt of the Earth's axis, and changes in the amount of solar radiation reaching the Earth.