vernal equinox

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vernal equinox

The vernal equinox marks the first day of spring in the Northern Hemisphere.

Definition

Noun: 1. The precise moment when the Sun crosses the celestial equator moving northward: This astronomical event marks the beginning of spring in the Northern Hemisphere. It is one of two points in the sky (equinoctial points) where the ecliptic and celestial equator intersect. 2. The date (approximately March 20 or 21) on which this event occurs: This date is characterized by nearly equal periods of daylight and darkness.

Usage Examples
  • Noun:
    • The vernal equinox occurs when the Sun's center passes through the celestial equator.
    • Many cultures celebrate festivals around the time of the vernal equinox.
    • Day and night are of approximately equal length on the vernal equinox.
Advanced Usage
  • "The March equinox": A common alternative name for the vernal equinox.
    • The March equinox marks the beginning of autumn in the Southern Hemisphere.
  • In a broader, often poetic sense, it can symbolize renewal, balance, or the start of a new cycle.
    • The poem uses the vernal equinox as a metaphor for rebirth.
Variants and Related Words
  • Equinox (n): The general term for either of the two times each year (vernal and autumnal) when day and night are of approximately equal length.
  • Autumnal equinox (n): The equinox occurring in September, marking the start of autumn in the Northern Hemisphere.
  • Solstice (n): Either of the two times in the year when the Sun reaches its highest or lowest point in the sky at noon, resulting in the longest or shortest day.
Synonyms
  • March equinox
  • Spring equinox
  • First point of Aries (an older astronomical term, though the point is now in Pisces due to precession)
Related Concepts and Phrases
  • Celestial equator: The projection of Earth's equator onto the celestial sphere.
  • Ecliptic: The apparent path of the Sun across the celestial sphere over the course of a year.
  • Precession of the equinoxes: The slow, cyclical shift of the equinoctial points along the ecliptic, which changes the constellation in which the equinox occurs over long periods.
vernal equinox

The vernal equinox marks the first day of spring in the Northern Hemisphere.

Noun
  1. (astronomy) the equinoctial point that lies in the constellation of Pisces
  2. March 21

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