Definition

Noun: - Kepler's law of planetary motion: In astronomy, one of three fundamental empirical laws describing the motion of planets around the Sun, formulated by the German astronomer Johannes Kepler in the early 17th century. These laws are based on the detailed observational data of Tycho Brahe.

Usage

• Noun:
  • Kepler's law of planetary motion provides a mathematical description of a planet's orbit.
  • Understanding Kepler's law of planetary motion was a crucial step in the development of classical mechanics.
  • The three laws are often referred to collectively as Kepler's laws of planetary motion.

Advanced Usage

• "Kepler's First Law (Law of Ellipses)": States that the orbit of a planet is an ellipse with the Sun at one of the two foci.
  • Kepler's First Law of planetary motion describes the shape of a planet's path.
• "Kepler's Second Law (Law of Equal Areas)": States that a line segment joining a planet and the Sun sweeps out equal areas during equal intervals of time.
  • Kepler's Second Law of planetary motion explains the varying speed of a planet in its orbit.
• "Kepler's Third Law (Law of Harmonies)": States that the square of the orbital period of a planet is directly proportional to the cube of the semi-major axis of its orbit.
  • Kepler's Third Law of planetary motion allows astronomers to relate a planet's distance from the Sun to its year.

Variants and Related Words

• Kepler's laws (n): The common collective term for the three laws of planetary motion.
  • Kepler's laws revolutionized our understanding of the solar system.
• Keplerian (adj): Pertaining to or in accordance with Kepler's laws.
  • The satellite was placed into a Keplerian orbit.

Synonyms

• Kepler's laws: The most direct synonym for the collective set.
• Laws of planetary motion: A more general term, though it specifically refers to Kepler's formulation in this context.

Related Phrases

• "To obey Kepler's laws": To move in accordance with the principles described by Kepler.
  • All planets in our solar system obey Kepler's laws.
• "Derived from Kepler's laws": Originating or calculated based on these principles.
  • Newton's law of universal gravitation was derived from Kepler's laws.

Noun

1. (astronomy) one of three empirical laws of planetary motion stated by Johannes Kepler