Why does the tarot know astrology?
The short answer: the tarot we use today was assembled by occultists who were already astrologers. Eliphas Lévi (1850s) paired the twenty-two Majors with the twenty-two Hebrew letters. The Hermetic Order of the Golden Dawn (1888) took Lévi's idea, re-lettered it with the Fool on Aleph, and walked it onto the Tree of Life — letters became paths, paths acquired planetary and zodiacal rulers, the decans locked onto the pips. Waite-Smith (1909) and Crowley-Harris (1944) both inherited that skeleton.
So when a Magician falls in your spread, the reading is already half-astrological — Mercury is in the room. When the Nine of Swords falls, the second decan of Gemini is in the room, with Mars as its inner ruler. You don't need a birth chart to read the tarot, but you cannot escape the wheel that shaped the images.
“The deck is a calendar the images forgot to print.”
The 22 Majors · Planet, Sign, Element
Seven trumps take a planet, twelve take a sign, three hold an elemental Mother letter. Modern authors have added Uranus / Neptune / Pluto to the three Mother-letter trumps for an extended ten-planet deck. Both columns below are correct — pick the one your tradition uses.
0 · The Fool
VIII · Strength
XII · The Hanged Man
XX · Judgement
The 36 Decans · Pip 2 – 10
Each of the four suits (2 – 10) gives you nine cards; across four suits that is thirty-six — exactly one card per decan. The assignment is not arbitrary: the Chaldean planetary cycle turns through the decans like a clock-hand, and the card that lands on each face inherits that planet's quality inside that sign.
A decan (from Greek dekanos, "chief of ten") is a 10° wedge of the ecliptic — three to a sign, thirty-six to the zodiac. Each decan covers roughly ten calendar days. The division is older than the tarot: Egyptian astronomers used thirty-six decanal star-groups to tell the hours of the night some four millennia before Crowley picked up a pen.
The Chaldean order runs Saturn → Jupiter → Mars → Sun → Venus → Mercury → Moon → and loops. Starting with Mars on Aries 1 (because Mars is Aries's traditional ruler), the planetary sequence runs five and a seventh times round while the decans walk the zodiac once — ending Pisces 3 on Mars, closing the circle.
Turn the wheel
The 16 Courts · Bridging the Elements
Each of the twelve senior courts (King · Queen · Knight) rules a 30° arc that starts in the last decan of one sign and runs into the first two decans of the next — a deliberate offset that makes every court a bridge between two elements. The four Pages ride outside the decan wheel: each rules a quadrant of the heavens around the pole, not a run of signs, so no degree boundary.
In the Golden Dawn's Book T the four court figures are King (mounted), Queen, Prince (in a chariot) and Princess. Lunarcana keeps the Rider–Waite–Smith names and matches them by element: the GD King, Fire of the suit, is our Knight; the GD Prince, Air of the suit, is our King; the Queen stays the Queen; the GD Princess is our Page. (Crowley's Thoth deck renamed the mounted King "Knight".)
Your sun-sign tarot card
Find the decan your Sun falls into — ten-degree slices of your sign, not the whole thirty. (Born in the first ten days? First decan. Middle ten? Second. Last ten? Third.) The pip card for that decan is your sun-sign card: the small-arcana image closest to how your central fire expresses.
Example: born August 15th — Sun in Leo, third decan (Aug 12–22), ruled by Mars. Your sun-sign card is the Seven of Wands — the defender of hard-won ground. This is a reading lens, not a horoscope — a single card cannot describe a person, only lend a question to the year.
Glyph legend
Seven traditional planets plus three modern outer bodies, twelve signs with element and modality. Every glyph here is typeset in text-variation mode (VS-15) — you should see an ivory outline rather than an Apple color emoji.
· Planets ·
· Zodiac ·
Aries
Fire · Cardinal
Mar 21 – Apr 20
Taurus
Earth · Fixed
Apr 21 – May 20
Gemini
Air · Mutable
May 21 – Jun 20
Cancer
Water · Cardinal
Jun 22 – Jul 21
Leo
Fire · Fixed
Jul 22 – Aug 22
Virgo
Earth · Mutable
Aug 23 – Sep 22
Libra
Air · Cardinal
Sep 23 – Oct 22
Scorpio
Water · Fixed
Oct 23 – Nov 22
Sagittarius
Fire · Mutable
Nov 23 – Dec 21
Capricorn
Earth · Cardinal
Dec 22 – Jan 19
Aquarius
Air · Fixed
Jan 20 – Feb 18
Pisces
Water · Mutable
Feb 19 – Mar 20
Further reading
Moon phases
The eight phases as a daily ritual companion to the zodiac year.
Elements
Fire · Water · Air · Earth — the deeper alphabet beneath the signs.
Court cards
How the sixteen courts walk the zodiac's four-element bridges.
Numerology
The ten pip stages that fit the ten-degree decans — shape meeting time.
Timing & Rhythm
How readers turn these decans into rhythm — without forecasting dates.
Planets
All ten planets reversed-indexed: see every card each ruler touches across majors, decans, and courts.
Zodiac
Twelve signs as navigable hubs — each gathers its major, three decan pips, and a court cusp-span.