first point of aries: meaning, definition, pronunciation and examples
Very low (specialist/technical)Technical/Astronomical
Quick answer
What does “first point of aries” mean?
The point on the celestial sphere where the Sun crosses the celestial equator moving northward, marking the vernal equinox.
Audio
Pronunciation
Definition
Meaning and Definition
The point on the celestial sphere where the Sun crosses the celestial equator moving northward, marking the vernal equinox.
Although named for the constellation Aries where it was historically located, it is now in Pisces due to precession; used as the zero point for measuring right ascension and celestial longitude in astronomy and astrology.
Dialectal Variation
British vs American Usage
Differences
No significant differences in meaning or usage. The term is standard in international astronomical literature.
Connotations
Technical, precise, historical. In non-technical contexts, sometimes associated with astrology.
Frequency
Extremely rare outside astronomy, astrophysics, and advanced astrology texts.
Grammar
How to Use “first point of aries” in a Sentence
The [first point of Aries] is defined as...[Right ascension] is measured from the [first point of Aries].Vocabulary
Collocations
Usage
Meaning in Context
Academic
Used in astronomy, astrophysics, and geodesy courses and papers to define coordinate systems.
Everyday
Virtually never used.
Technical
Essential term in astronomical almanacs, satellite orbital mechanics, and celestial navigation.
Vocabulary
Synonyms of “first point of aries”
Strong
Neutral
Weak
Vocabulary
Antonyms of “first point of aries”
Watch out
Common Mistakes When Using “first point of aries”
- Using it to refer to the actual constellation Aries.
- Forgetting that it is no longer in the constellation Aries.
- Confusing it with the autumnal equinox point.
FAQ
Frequently Asked Questions
No. Due to the precession of the equinoxes, it has moved into the neighbouring constellation Pisces.
They are essentially the same event/location. The 'first point of Aries' is the specific coordinate point on the celestial sphere that defines the vernal equinox.
It serves as the origin (0 hours) for the celestial coordinate of right ascension, similar to how the Greenwich Meridian is 0° longitude on Earth.
Western tropical astrology uses the moving point (relative to the seasons), defining 0° Aries as the vernal equinox. Sidereal astrology uses a fixed point relative to the stars.
The point on the celestial sphere where the Sun crosses the celestial equator moving northward, marking the vernal equinox.
First point of aries is usually technical/astronomical in register.
First point of aries: in British English it is pronounced /ˌfɜːst pɔɪnt əv ˈeə.riːz/, and in American English it is pronounced /ˌfɜːrst pɔɪnt əv ˈeriːz/. Tap the audio buttons above to hear it.
Learning
Memory Aids
Mnemonic
Think of a map of the sky; the 'First Point of Aries' is like the Greenwich Meridian (0° longitude), but for space. 'First' because it's the starting point for measurements.
Conceptual Metaphor
A FIXED POINT ON A MOVING CANVAS (the reference point itself slowly moves due to precession).
Practice
Quiz
What is the current astronomical location of the first point of Aries?