Description: The orbital period is the time it takes for an object to make one complete orbit of another object. Another way of stating this is that it is the time it takes for an object to arrive back to the same point in its orbit. This could be a planet going around a central star (for example, Earth orbiting the Sun); it could be a moon orbiting around a planet; it could be a star, group of stars, or nebulae going around the center of a galaxy; it could be two (binary) stars orbiting their common center of mass.

Related Terms:

• Binary Star
• Gravity
• Kepler's Laws
• Orbit
• Solar Wind

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

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