Western Horoscope (西洋星座)

Natal Chart Decoded — Planets, Signs, and Houses

Overview

Western Horoscope analysis derives a natal chart from a birth date, computing Sun sign, Moon sign, Ascendant, and planetary positions across the twelve zodiac signs. Each placement carries elemental, modal, and dignity information that together paint a detailed portrait of character, potential, and life themes.

Origin & history

Western horoscopic astrology traces its roots to ancient Babylon (circa 700 BCE), where court astronomers first began casting individual birth charts. The tradition was systematised by Hellenistic scholars — most notably Claudius Ptolemy in his 2nd-century CE Tetrabiblos — and transmitted through Arabic, medieval European, and Renaissance channels to the modern era.

From Babylonian omen astrology to Hellenistic natal charts, through the Arabic translations of the 9th century and the Renaissance revival, Western astrology reached its modern form in the 20th century through the psychological astrology of Dane Rudhyar and Liz Greene, who integrated Jungian archetypes with traditional planetary symbolism.

How it works

The askTIAN horoscope endpoint takes a birth date and computes the positions of the Sun, Moon, Mercury, Venus, Mars, Jupiter, and Saturn in the twelve zodiac signs. It returns dignities (domicile, exaltation, detriment, fall), element and modality profiles, and an LLM-generated synthesis narrative.

Good for

• Self-understanding and personality insight
• Career and vocation guidance
• Relationship compatibility
• Life timing and transits
• Psychological self-reflection

Use cases

Natal Chart Reading

Generate a full natal chart breakdown for any birth date, returning Sun, Moon, Ascendant, and planetary placements with dignity analysis and a synthesised interpretation.

Personality Profiling

Use the element and modality profile to understand a person's dominant energies — fire/earth/air/water balance and cardinal/fixed/mutable distribution.

Synastry and Compatibility

Compare two natal charts to assess relationship dynamics — how one person's Sun, Moon, Venus, and Mars placements interact with another's, revealing areas of attraction, friction, and long-term harmony.

Key terms

Sun Sign

The zodiac sign occupied by the Sun at birth — the most widely known astrological placement, representing core identity and life purpose.

Ascendant (Rising Sign)

The zodiac sign rising on the eastern horizon at the moment of birth, representing the persona and how one presents to the world.

Planetary Dignity

A measure of a planet's strength in a given sign: domicile (strongest), exaltation, detriment, or fall (weakest).

Aspect

An angular relationship between two planets measured in degrees of the zodiac — conjunction (0°), sextile (60°), square (90°), trine (120°), and opposition (180°) — describing whether their energies blend harmoniously or in tension.

API

The askTIAN Western Horoscope API computes Sun, Moon, Ascendant, and five classical planet positions for any birth date, returning dignities, element/modality profiles, and an LLM-generated synthesis.

Endpoint: POST /trpc/horoscope.calculate — 1 TIAN Points. See the API documentation and Playground.