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equinoctial

equinoctial

9.9
A circle in the sky halfway between the sky's north and south poles
  • noun
  • /ˌɛkwɪˈnɒkʃəl/
  • Specialized
translation icon : ecuador celeste
  • In astronomy classes, we learn about the equinoctial line that divides the northern and southern celestial hemispheres.

Examples

  • Ancient astronomers mapped the equinoctial to chart the movement of the stars.

  • Many star charts prominently display the equinoctial as a reference point.

  • The sun crosses the equinoctial twice a year at the equinoxes.

  • The sun crosses the equinoctial at noon.

  • The equinoctial marks the celestial equator.

  • The equinoctial regions experience minimal variation in day length throughout the year.

  • Understanding the equinoctial helps astronomers track celestial movements more accurately.

Synonyms

celestial equator
vsequinoctial
  • Specialized
1 8.5

An imaginary circle around the sky above Earth's equator

is the same concept but often used as the common or standard name
equinoctial circle
vsequinoctial
  • Specialized
9.9

An imaginary circle across the sky midway between the north and south poles

is the same concept but expressed in a different term or phrasing
equinoctial line
vsequinoctial
  • Specialized
9.9

An imaginary line in the sky that matches Earth's equator and divides the sky into north and south

is the same idea but appears as an alternative phrasing or variant

Compounds

equinoctial circle
  • Specialized
9.9

An imaginary circle across the sky midway between the north and south poles

equinoctial line
  • Specialized
9.9

An imaginary line in the sky that matches Earth's equator and divides the sky into north and south

equinoctial point
  • Specialized
9.9

A point in the sky where the Sun crosses the Earth's equator at spring or autumn equinox

A strong rainstorm that happens around the spring or autumn equinox

equinoctial year
  • Specialized
8.6

The time Earth takes to go from one spring equinox to the next, about 365.24 days

Surface Forms

equinoctial singular
equinoctials plural

Etymology

Equinoctial names the big circle in the sky halfway between the North and South poles, and the word comes from Latin aequus 'equal' and nox 'night'. This circle was called the 'equinoctial' because the sun crosses it at the times when day and night are equal.