What Rahu and Ketu mark
The Moon’s orbital plane tilts relative to the ecliptic, the plane used as a reference for solar and planetary longitude. Its two intersections with that reference plane are the lunar nodes. In Jyotish, the ascending node is called Rahu and the descending node Ketu. The two points remain opposite each other on a zodiac circle, so a Rahu entry into one 30° rashi is a Ketu entry into the opposite rashi at the same instant. The node is a computed direction, not a luminous body to look for in a telescope.
Eclipses occur only when a New or Full Moon is sufficiently close to this axis. That astronomical relation explains why the nodes appear in both ephemerides and long-standing astrological traditions. An ingress calendar by itself does not calculate an eclipse, show its visibility, or establish what an individual will experience. The personal interpretations sometimes attached to Rahu and Ketu are traditional readings, not properties measured by the longitude formula.
Mean and true are different coordinates
The mean node smooths short-term oscillations in lunar orbital motion. Our mean ascending-node longitude uses the Meeus polynomial in the mean ecliptic and equinox of date. The true node comes from the intersection of the instantaneous geocentric Moon-orbit plane and the true ecliptic of date, using a lunar position and velocity vector from Astronomy Engine 2.1.19. The true node can briefly move forward even though the mean node moves steadily backward over these years. Our calculations do not call Swiss Ephemeris and are not labeled Swiss Ephemeris outputs.
The website’s existing lunar-node module returns both tropical longitudes. To convert them to a sidereal zodiac, the calendar subtracts the matching form of its approximate Lahiri ayanamsa: the mean value from the mean node and the nutation-adjusted true value from the true node. It reduces the result to 0°–360° and divides by 30° to name one of twelve rashis. Ketu is the antipode of Rahu. This convention is printed beside results because another ayanamsa or lunar ephemeris can move a boundary time.
Why 2026 produces two published dates
Drik Panchang’s Rahu Gochar page for 2026 lists a mean Rahu entry into Makara on December 5 at 19:28 and a True Rahu entry on November 25 at 16:34 for an Indian city using UTC+05:30. Its Ketu page pairs those instants with entry into Karka. This public example is a date-level benchmark for our independent calculation, not a table imported into the website. The exact local minute may differ because of lunar theory, ayanamsa definition, time scale, or rounding. To compare websites, first select the same node convention and convert both displayed clocks to UTC.
The publisher’s 2027 Rahu rashi page reports no new rashi entry that year. A calendar with no ingress rows is therefore possible and useful: the opening sign line says where Rahu and Ketu were at local New Year. A different date window or an alternate reference convention can change whether an event falls close to a civil-year edge.
Retrograde and possible direct re-entry
Mean Rahu generally moves backward through successive rashis. The true node oscillates around that slower trend and can be direct over short intervals. If a true node crosses a rashi boundary backward, forward, and backward again, this tool lists all crossings as separate instants rather than merging them into one “transit date.” A direct re-entry is a change in calculated ecliptic longitude, not a second physical orbit or a guaranteed event. Ketu mirrors Rahu across the zodiac, so the output prints a pair of rows for every instant.
The browser scans the selected local civil year in three-hour windows, with a midpoint check inside each window. A sign change is narrowed to a fifteen-second bracket by bisection, then both UTC and local clocks are displayed to the minute. A very brief out-and-back fully contained between samples could be missed. The method is adequate for an educational rashi-boundary lookup, but is not a claim of exhaustive high-precision node-event certification. The CSV preserves each displayed pair of rows with the method and both clocks.
Time zones and calendar dates
The year starts at 00:00 on January 1 under the entered fixed UTC offset and ends at the next local January 1, exclusive. A crossing at the end belongs to the following year. The calculator does not infer a city, historical time-zone law, or daylight-saving change. The same UTC ingress can appear on adjacent local dates in different countries. For comparisons, use the UTC column, then check the local offset and whether a source labels a sunrise-based Panchang day rather than a midnight-based civil day.
Common questions
Which node should I choose?
Choose the convention used by the chart or tradition you intend to compare. The site’s own Vedic birth chart currently uses the mean node and says so. The true option is useful when checking a publication that explicitly labels “True Rahu.” Neither choice is interchangeable at a sign edge.
Why are Rahu and Ketu on the same date?
They are opposite ends of one node axis. When one crosses a sidereal 30° boundary, the other crosses the opposite boundary at exactly that modeled instant.
Does a rashi ingress predict an outcome?
No. This page calculates a coordinate crossing. Interpretations vary by school, chart context, and practitioner; the calendar does not determine an outcome or assign personal advice.