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Rahu and Ketu
Rahu and Ketu are not physical bodies. They are the two points where the Moon's orbital plane intersects the ecliptic — the apparent path of the Sun. These intersection points are called the lunar nodes. They are always exactly 180° apart. They move backward through the zodiac, completing one cycle in approximately 18.6 years.
Their astronomical nature gives them no mass, no light, no orbital motion of their own. And yet Jyotish has placed them at the center of its most important predictive system — the Vimshottari Dasha. That should say something about how seriously the tradition takes them.
The Geometry§
Rahu — North Node (☊) is the ascending node: the point where the Moon crosses the ecliptic while moving northward. When the Moon passes through Rahu, solar and lunar eclipses become possible — the mythology associates Rahu with swallowing the Sun and Moon.
Ketu — South Node (☋) is the descending node: always directly opposite Rahu. Where Rahu amplifies, Ketu dissolves. Where Rahu craves, Ketu has already been and let go.
The Mythological Frame§
The tradition gives Rahu and Ketu a vivid origin story. A demon named Svarbhānu disguised himself as a god during the churning of the cosmic ocean and drank the nectar of immortality. Vishnu, alerted by the Sun and Moon, severed him with his discus. But the demon had already swallowed the nectar — both halves were immortal. The head became Rahu; the headless body became Ketu.
This image encodes the astrological distinction precisely: Rahu has a head but no body — it obsesses, craves, analyzes, but never fully digests. Ketu has a body but no head — it acts on instinct and accumulated pattern, without deliberation or ego.
Rahu — Amplification and Desire§
Rahu expands what it touches. In the chart, it represents worldly desire, ambition, the hunger for experience that has not yet been satisfied. It is associated with foreignness, unusual paths, obsession, and the crossing of cultural or social boundaries.
| Signifies | Foreigners, unconventional paths, obsession, illusion, worldly ambition, mass trends, technology, sudden events |
| Acts like | Saturn when alone; amplifies the nature of any planet it conjoins; can behave like Jupiter in expansive contexts |
| Dasha | 18 years — the longest in Vimshottari. Often intense worldly engagement, achievement through unusual means, or confrontation with illusion. |
Ketu — Dissolution and Liberation§
Ketu separates. It represents what has already been experienced and is no longer craved — past-life patterns, accumulated wisdom, spiritual inclination, and the part of life where worldly hunger is absent. Where Rahu grasps, Ketu has already let go or never wanted in the first place.
| Signifies | Liberation, spirituality, hidden knowledge, past-life patterns, separation, surgery, ascetics, renunciation, investigation |
| Acts like | Mars when alone — sharp, cutting, sudden. Gives strong investigative ability. Frequently grants unusual insight in the 8th or 12th house. |
| Dasha | 7 years — the shortest in Vimshottari. Often a period of separation, retreat, spiritual deepening, or the conclusion of a long chapter. |
The Nodal Axis§
Rahu and Ketu always occupy opposite houses, forming an axis through the chart. Rahu in the 7th house / Ketu in the 1st: the native is pulled toward others while the inner self is the domain of dissolution and detachment. The axis describes a fundamental push-pull in how the life energy flows.
The sign and house placement of Rahu and Ketu, and the condition of the planet ruling those signs, tells the interpreter where the native's craving is directed and where their reservoir of prior mastery lies.
True Node vs. Mean Node§
| Mode | Description |
|---|---|
| True Node | The actual instantaneous position of the node — oscillates slightly as it moves. Can briefly move forward. |
| Mean Node | A smoothed average position — always retrograde, no oscillation. |
The difference is rarely more than 1–2 degrees, but it can occasionally place the node in a different sign. Moonketu uses True Node by default and lets you switch to Mean Node in the settings drawer.
The nodes have no rulership over signs, no mool trikon, no exaltation by universal agreement — and yet they preside over 25 of the 120-year Vimshottari cycle (Rahu 18 + Ketu 7). They are the shadow planets: invisible, inescapable, and deeply embedded in the mathematics of the sky. The individual pages for Rahu and Ketu go deeper into their house-by-house expressions.