Description: Rotation is the motion of an object around an imaginary line, which is called the axis of rotation. As the object rotates, each of its different parts keeps exactly the same distance from the axis of rotation. In general, stars (including the Sun), planets, moons, or asteroids will rotate around a fixed axis. Earth rotates around Earth's axis, which is the imaginary straight line passing through Earth's North and South Poles. The Earth's rotation is responsible for the changing view of the night sky that every observer standing on the Earth's surface will see, with new stars continually rising along the eastern horizon, and setting along the western horizon. The fact that the Sun appears to move across the sky during the day, rising in the east and setting in the west, is also a consequence of the Earth's rotation.

Related Terms:

• Night

Term and definition status: This term and its definition have been approved by a research astronomer and a teacher

The OAE Multilingual Glossary is a project of the IAU Office of Astronomy for Education (OAE) in collaboration with the IAU Office of Astronomy Outreach (OAO). The terms and definitions were chosen, written and reviewed by a collective effort from the OAE, the OAE Centers and Nodes, the OAE National Astronomy Education Coordinators (NAECs) and other volunteers. You can find a full list of credits here. All glossary terms and their definitions are released under a Creative Commons CC BY-4.0 license and should be credited to "IAU OAE".