Measure the Sun against a named zodiac
The Sun’s apparent geocentric ecliptic longitude is first calculated for a UTC instant. An ayanamsa is subtracted to put that longitude in a sidereal zodiac. This calendar uses the site’s approximate Lahiri method. It divides the resulting 360° circle into twelve equal 30° rashis and searches for entry into each next sector. A rashi here is an equal angular division, not the visible outline of a constellation.
The Positional Astronomy Centre’s Rashtriya Panchang explanation says the national almanac reports Sun and Moon transits into nirayana rashis using a variable ayanamsa. Its publication overview names Sun transits as an almanac item. The official 2026–2027 transit table offers a point of comparison for named entries. These sources establish terminology and almanac scope; this site computes its own times.
One entry instant, different local dates
Suppose an ingress occurs at 2026-04-13 23:30 UTC. A fixed UTC+05:30 clock reads 2026-04-14 05:00; a UTC−07:00 clock reads 2026-04-13 16:30. These are two labels for one event. The selected civil year begins at January 1 local midnight under the entered fixed offset and ends at the next local New Year midnight. A boundary exactly at the ending midnight belongs to the following year, so neighboring year tables do not duplicate it.
A fixed offset does not supply historical daylight-saving rules. A seasonal clock change within the year makes one entered offset inappropriate for some rows. In that case, use the UTC timestamp and convert each entry with your location’s actual time-zone rule.
Calculation and precision
The browser uses bundled Astronomy Engine 2.1.19 for the apparent geocentric Sun vector and its true-ecliptic-of-date longitude. It subtracts the site’s approximate Lahiri ayanamsa: a J2000 reference value advanced with an IAU 2006 precession approximation and nutation. Daily samples detect the next 30° crossing; binary refinement narrows it to a 15-second bracket. The display truncates to a minute rather than claiming second-level agreement.
This calculator does not run Swiss Ephemeris. A different ayanamsa, ephemeris, or coordinate convention can shift the event minute, especially when comparing a crossing near local midnight with a published almanac. The table covers only 2026–2027.
An ingress is not a festival date
Drik Panchang’s Sankranti calendar presents local observance information beside ingress times. This page reports only the longitude crossing and two clock labels. It does not calculate auspicious periods, sunrise-based assignment, a regional festival date, or a ritual recommendation. The daily panchanga handles a local sunrise context for its own five calendar limbs, but it does not turn an ingress into a universal observance rule.
Frequently asked questions
Why can Mesha Sankranti and a tropical Aries ingress differ?
The tropical Aries boundary follows the equinox, while the sidereal Aries boundary uses a specified ayanamsa. The dates consequently differ. Keep the two zodiac frames separate when comparing tables.
Does my latitude change the listed instant?
Not in this geocentric longitude calculation. Latitude can matter for a local sunrise or observance rule; the chosen fixed offset changes only the displayed civil clock and year-edge selection.
Why might another panchang list a different minute?
Check the other calendar’s ayanamsa, geocentric or other position convention, clock zone, and whether its time marks entry or an observance window. This site’s approximate Lahiri formula is not a published almanac computation.