Pronunciation: [plˈanɪtəɹi ˈɔːbɪt] (IPA) 
Planetary orbit is a term used in astronomy to describe the path that a planet takes as it orbits around a star. The word is spelled with a /ˈplænətəri ˈɔrbɪt/ in IPA phonetic transcription. In this spelling, the "t" in "planet" is pronounced as a flap sound, while the "ary" in "planetary" is pronounced as a schwa followed by an r sound. The stress is on the second syllable of "planetary" and "orbit."
A planetary orbit refers to the path or trajectory followed by a planet as it revolves around a star, usually in the context of our solar system. It is a fundamental concept in astronomy and planetary science that describes the gravitational relationship between celestial bodies.
Planetary orbits are primarily governed by the gravitational pull of the star they orbit, commonly known as the central or parent star. This gravitational force acts as a centripetal force and keeps the planets in their respective orbits. The shape of a planetary orbit is generally elliptical, with the star located at one of the two foci of the ellipse.
The major properties of a planetary orbit include the semimajor axis, which represents the average distance between the planet and its star, and the eccentricity, which describes how elongated the elliptical path is. These properties determine the period, or the time taken for a planet to complete one orbit around its star, as well as the velocity of the planet at each point along its path.
The study of planetary orbits is crucial for understanding the dynamics and evolution of the solar system. Astronomers use observations and mathematical models to determine the characteristics of planetary orbits, including their inclination with respect to the plane of the star's rotation and any deviations caused by external factors such as other celestial bodies. Overall, the concept of a planetary orbit plays a pivotal role in unraveling the mysteries of our solar system and beyond.
The word "planetary" is derived from the Latin word "planeta" which means "wandering star". The term "orbit" also originates from Latin, derived from the word "orbis" meaning "circle" or "disk". In astronomical context, "planetary orbit" refers to the path followed by a planet or other celestial body as it revolves around a star in a circular or elliptical shape.
