Every other graha moves forward. Rahu and Ketu move backward — a shadow axis that never breaks its 180-degree symmetry, sweeping through your chart's houses roughly every eighteen months.
Rahu and Ketu are shadow points, not physical bodies, marking the two places where the Moon's orbit crosses the Sun's apparent path. One structural consequence of that geometry is that they always move retrograde — backward through the zodiac, sign by sign in reverse order — unlike every other graha, which normally moves forward and only turns retrograde occasionally. This backward motion is completely normal for Rahu and Ketu; it is simply how the lunar nodes always transit.
Rahu and Ketu each spend approximately eighteen months in a sign, and because they move steadily backward with very little variation in speed, their full transit cycle through all twelve signs takes close to eighteen years — a rhythm that sits between Jupiter's twelve-year cycle and Saturn's roughly thirty-year cycle.
Because Rahu and Ketu mark the two points where the Moon's path crosses the Sun's, they are always positioned exactly 180 degrees apart — directly opposite signs and, in a birth chart, directly opposite houses. Wherever transiting Rahu sits, transiting Ketu is always found in the exact opposite sign, at the exact same time, moving at the exact same pace. Astrologers therefore rarely read them separately; the pair is usually discussed together as a single moving axis.
Rahu is classically linked with sudden, often unplanned change, ambition, obsession and worldly craving — themes pulling a person outward and forward, sometimes without full regard for consequence. Ketu carries the opposite pull: detachment, release, endings and a quieter, more spiritual withdrawal from whatever Rahu's house of the moment has been chasing. This complementary mythology — one node driven by hunger for the material, the other by an instinct to let go — is explored in more depth in the article on the rebirth cycle, but the short version relevant to transit is this: wherever the Rahu-Ketu axis currently falls in your chart, you can usually expect one house's affairs to feel unusually urgent and amplified (Rahu's side) while the exactly opposite house's affairs feel like they're quietly being released or completed (Ketu's side).
Because the transiting Rahu-Ketu axis takes about eighteen years to travel all the way around the zodiac, it eventually returns to cross directly over your own natal Rahu-Ketu axis roughly every eighteen years. This return is often watched as a marker of major life-direction shifts — a point where the very themes your birth chart originally staged around obsession and release come back around for a fresh, often pivotal round.
Rahu never travels alone, and it never travels forward for long without Ketu quietly settling the account on the opposite side of the sky.
Check Rahu and Ketu's live transit against your chart — See which houses transiting Rahu and Ketu currently occupy in your chart, and what themes that axis is highlighting right now. Download the App for Live Transits
Rahu and Ketu are the two points where the Moon's orbital path crosses the Sun's apparent path, and the geometry of that crossing naturally regresses backward through the zodiac over time — so retrograde motion is their normal, constant state.
Approximately eighteen months per sign, adding up to a full zodiac cycle of roughly eighteen years.
No — they are always exactly 180 degrees apart, meaning they are always in directly opposite signs of the zodiac at every moment, never together and never in unrelated signs.
This happens roughly every eighteen years and is generally read as a significant marker of major life-direction change, since it represents the node axis completing a full cycle back to its original birth position.
Not necessarily. Rahu's transit is associated with sudden change and heightened ambition in whichever house it occupies, which can manifest as opportunity or upheaval depending on the natal strength of Rahu and the houses involved.