Definition

Noun: - A principle in celestial mechanics: This law states that for any planet orbiting the sun, an imaginary line connecting the planet to the sun sweeps out equal areas in equal intervals of time. It describes how a planet's orbital speed varies depending on its distance from the sun.

Usage

• This term is used in the context of astronomy and physics to describe a fundamental property of orbital motion.
• It is often introduced when discussing Kepler's laws of planetary motion.

Examples

• Noun:
  • Kepler formulated the law of equal areas based on Tycho Brahe's observational data.
  • The law of equal areas explains why a planet moves faster when it is closer to the sun.

Advanced Usage

• "To obey/conform to the law of equal areas": Describes orbital motion that follows this principle.
  • All planets in our solar system obey the law of equal areas.

Variants and Related Words

• Kepler's second law: This is the common name for the law of equal areas. They are synonymous terms.
  • Kepler's second law, also known as the law of equal areas, was a revolutionary idea.

Synonyms

• Kepler's second law: The direct synonym.
• Law of areas: A less common but equivalent term.

Related Concepts (Not Phrasal Verbs or Idioms)

• Orbital velocity: The speed of an object in orbit, which changes according to this law.
• Perihelion: The point in an orbit closest to the sun, where speed is greatest.
• Aphelion: The point in an orbit farthest from the sun, where speed is slowest.

Noun

1. a law concerning the speed at which planets travel; a line connecting a planet to the sun will sweep out equal areas in equal times
   • Kepler's second law means that a planet's orbital speed changes with its distance from the sun