The earlier articles on Rahu and Ketu covered what the nodes symbolise in a birth chart, which is fixed at the moment of birth. Gochar (transit) is about where the nodes are now and which houses of a chart that position falls in. The positions are astronomy; what the tradition reads into a house crossing is interpretation, and a transit is not by itself an explanation for anything happening in someone's life.
What the Nodes Are
Rahu and Ketu are not bodies but points: the two places where the Moon's orbit crosses the ecliptic, the Sun's apparent path. Rahu is the ascending (north) node and Ketu the descending (south) node. Ketu is taken as exactly 180° from Rahu, so the two are always in opposite signs and change sign at the same moment.
Mean Node and True Node
There are two standard ways to give Rahu a longitude:
- Mean node. A smoothed position that moves steadily backward through the zodiac at about 19.3° a year, completing a circuit in about 18.6 years. Many Indian panchangs list Rahu this way, and this site's yearly transit pages use the mean node.
- True node. The instantaneous position, which wobbles around the mean node by up to about a degree and a half. It mostly moves backward but can briefly appear stationary or move forward.
Because of that wobble, mean-node and true-node tables can put a sign change several weeks apart. A transit table should say which one it uses, and which zodiac. In Vedic practice that is the sidereal zodiac, here with the Lahiri ayanamsa.
The backward motion is real. The nodes regress because the Sun's gravity slowly turns the plane of the Moon's orbit. "Always retrograde", though, is strictly true only of the mean node.
How Long the Axis Stays in a Sign
With the mean node, 18.6 years divided by 12 signs gives about 18 to 19 months per sign. Rahu's 18-year Mahadasha in the Vimshottari system is a separate convention that happens to have a similar number; the two are not connected.
On this site's mean-node calculation with the Lahiri ayanamsa, Rahu entered sidereal Aquarius (Ketu Leo) in mid-May 2025, and moves into Capricorn (Ketu Cancer) in early December 2026. True-node sources will show somewhat different dates.
Counting the Houses: A Worked Example
Transit houses are counted with whole signs from two reference points, the natal Moon sign and the Lagna. An illustrative chart with Leo Lagna and the Moon in Taurus:
- Rahu in Aquarius, Ketu in Leo (from mid-May 2025). From the Leo Lagna, Rahu is in the 7th and Ketu in the 1st. From the Taurus Moon, Rahu is in the 10th and Ketu in the 4th.
- Rahu in Capricorn, Ketu in Cancer (from early December 2026). From the Leo Lagna, Rahu is in the 6th and Ketu in the 12th. From the Taurus Moon, Rahu is in the 9th and Ketu in the 3rd.
Because the nodes are opposite, the two houses in each pair are always seven signs apart (1st/7th, 4th/10th, 6th/12th, 3rd/9th). The Moon count needs an accurate Moon sign; the Lagna count needs an accurate birth time.
How the Tradition Reads a House Crossing
What follows is traditional interpretation, not a tested prediction. Interpreters associate Rahu with appetite, novelty and the unfamiliar in the house it crosses, and Ketu with detachment or completion in the opposite house. They read the pair together: in the example above, Rahu across the 7th and Ketu across the 1st is described in terms of partnership themes in the foreground and less focus on the self. The tradition does not call any of the twelve pairings simply good or bad. It qualifies every reading by the natal strength of the nodes, the running Dasha and faster transits.
Common Misconceptions
"A node transit through a house guarantees trouble there." The tradition itself does not claim this. A house crossing is a calculated position, and the reading is always conditional on the rest of the chart.
"It is the same as Kaal Sarp Dosha." No. Kaal Sarp Dosha is a natal pattern, fixed at birth. A node transit is a moving position that passes through some pair of houses in every chart, all the time.
"Eighteen months in a sign means eighteen months of intensity." The sign position is steady, but that says nothing measurable about how a period feels. Even within the tradition, other transits and the Dasha are layered on top.
Traditional Remedies
The remedies traditionally associated with the nodes include Nag Panchami observances, Rahu-Ketu shanti pujas, and Ganesha or Durga worship. They belong to religious practice. If a period brings real difficulties, practical help from the relevant qualified professional comes first, whatever the transit. A reflection drawn from the symbolism, not a prediction.
Sources & References
Astronomical data: This site's yearly transit pages give Rahu by the mean lunar node (the formula in Meeus, Astronomical Algorithms) with the Lahiri (Chitrapaksha) ayanamsa, and Ketu exactly opposite. Natal Moon sign and Lagna come from the astronomy-engine ephemeris. Birth chart reports do not yet compute natal node longitudes. See our Methodology for full technical detail.
Astrological tradition: The interpretations above draw on the sources named under Classical references below. Where an interpretation is not tied to a named source, it is AstroMystra's paraphrase of common practice among teachers of the tradition, not a verified rule of prediction. AstroMystra's specific phrasing, examples, and emphasis are its own.
Classical references: No single classical passage is claimed here as the authority for these conventions, which are applied differently between practitioners and lineages. The general framework of planets, signs and houses is described in Parashara's Brihat Parashara Hora Shastra (English translation by R. Santhanam, Ranjan Publications). Treat remedies and timing rules as traditional practice, not established fact.