Western Astrology

Western astrology is a family of Hellenistic, medieval, Renaissance, traditional, and modern practices. Most contemporary Western charts use the tropical zodiac, but zodiac choice alone does not define the tradition. Western sidereal astrologers also exist.

The shared natal-chart grammar

A Western natal reading usually combines:

• planets, including Uranus, Neptune, and Pluto in many modern schools,
• zodiacal signs,
• twelve houses,
• angular relationships called aspects,
• planetary rulership and dignity,
• the Ascendant, Midheaven, and other angles,
• and sometimes calculated points such as the lunar nodes or lots.

Traditional and modern schools can assign different emphasis or meaning to the same factor. A reproducible reading should identify its school, zodiac, house system, aspect set, rulership scheme, and allowed points.

Aspects

An aspect measures angular separation. The major Ptolemaic aspects are:

An orb defines how far from exact an aspect may be while still being counted. Schools differ on orb size, whether the aspect is applying or separating, and which minor aspects are included. Those choices should be inputs, not hidden assumptions.

Ptolemy's Tetrabiblos is an important primary witness for the classical planet, sign, and aspect framework; the Loeb translation is available through LacusCurtius.

Dignity, rulership, and condition

Traditional judgment asks whether a planet can act according to its nature and whether it has authority over the matter being judged. Sign rulership, exaltation, angularity, sect, speed, visibility, aspects, and house placement can all contribute. Modern psychological schools often place more emphasis on symbolic integration and personal experience.

Neither approach is captured by a list of generic planet keywords. The chart condition must be evaluated under one declared method.

Houses and angles

The Ascendant and Midheaven are location-dependent angles. House systems divide the local sphere or related arcs in different ways. Placidus, Porphyry, Equal, and Whole Sign houses can place the same planet in different houses without changing its zodiacal longitude.

Swiss Ephemeris documents the supported house calculation methods.

Western timing

Common Western timing tools include:

• transits,
• secondary progressions,
• solar-arc directions,
• annual profections,
• solar returns,
• and other traditional time-lord techniques.

These are not interchangeable with a planetary dasha. A transit follows the current sky; a progression or direction advances the natal figure by a defined symbolic rate; a profection assigns annual emphasis through a counting rule.

Relationship to Jyotisha

Western and Indian astrology share ancient astronomical and horoscopic vocabulary, but their later rule systems are not identical. Differences can include zodiac choice, nodes and outer planets, aspect doctrine, house lordship, divisional charts, nakshatras, dashas, yogas, and the order of judgment.

Ascendant currently focuses on sidereal Jyotisha calculations and a Parashari–Raman agent workflow. Its support for Placidus or Porphyry houses does not make it a complete Western astrology interpreter.