Jathakam basics: Rashi, Nakshatra, Pada and Lagna

A Jathakam begins with a birth instant and place. From those inputs, a calculator places the Moon, Sun and other grahas in a zodiac, identifies the Moon’s birth star, and finds the rising sign at the eastern horizon. This guide explains what the main labels on our Jathakam calculator mean and how to enter details that make the result useful.

Rashi: the Moon’s sign

Our Rashi display is the Moon’s sign in the sidereal zodiac. Each of the twelve signs spans 30° of zodiacal longitude. For example, a Moon longitude of 12° Taurus is in Taurus Rashi. This is different from a Sun-sign label: the Sun and Moon can occupy different signs at the same birth instant. Open the focused Rashi tool if you only need this result.

Nakshatra and Pada: a finer Moon position

The 360° zodiac is divided into 27 equal Nakshatras of 13°20′ each. Every Nakshatra is divided into four Padas of 3°20′ each. The birth star and Pada therefore come from the Moon’s calculated sidereal longitude, rather than from a separate place-name or date lookup. When the Moon is close to a division boundary, even a small difference in the calculated longitude can change the label. See the Nakshatra and Pada calculator and its precision note.

Lagna: the rising sign

Lagna is the zodiac position rising where the ecliptic meets the eastern horizon for the entered time and location. Unlike the geocentric Moon-sign calculation, it depends directly on the birthplace coordinates and changes through the day as Earth turns. A rough town-centre coordinate or uncertain birth time may change Lagna, particularly near a sign boundary. Our Lagna view reports the rising sign and degree; the chart currently uses whole-sign houses.

Grahanila: positions behind the labels

The Grahanila table shows a sign, degree, Nakshatra and Pada for the calculated grahas. Rahu is represented by a mean lunar node in the current method, with Ketu opposite it. This table lets you inspect the positions used by the summaries instead of treating a single label as the whole chart. It is a positional chart, not an automatic interpretation of every house or planetary relationship.

Entering a birthplace and time

• Enter the date and local clock time recorded for the birth. If the time is estimated, remember that Lagna can be especially sensitive to it.
• Search for a Kerala birthplace in English or Malayalam, or browse by district and taluk. Select a result; simply typing a place name does not confirm its coordinates.
• Check the selected point. Some revenue villages use a taluk reference point and a town may use an approximate centre. If you know the precise hospital or birth location, use the advanced latitude and longitude fields.
• Confirm the UTC offset at birth, especially for historical or non-Indian births. A present-day time-zone assumption might not apply to the recorded date.
• Read the degree and calculation note alongside each sign and star. Independently check a boundary-sensitive result before using it for a consequential decision.

A fixed example and what it proves

For a fabricated example at 00:00 IST on 15 August 1990, using 8.5241° N, 76.9366° E in Thiruvananthapuram and UTC+5:30, the current site displays Aries Lagna 28°54′, Taurus Moon 12°42′, and Rohini Pada 1. An independent Swiss Ephemeris Lahiri calculation of the same instant gives an ascendant of Aries 28°53′30.845″, which rounds to the site’s displayed Lagna minute. Its Moon longitude is Taurus 12°41′25.2425″, differing from our displayed Moon minute. The example tests specific inputs; it does not certify all dates, planets or boundary cases.

Why another chart may differ

A sidereal result depends on the chosen ayanamsa definition and ephemeris, the birth instant derived from the local time and historical offset, coordinates, node convention and rounding. Our V1 uses an approximate Lahiri reference model; the planetary degree or Pada near a boundary is provisional. The methods and limitations page identifies the current conventions. The Swiss Ephemeris programming documentation explains sidereal modes and reference calculations used for independent comparisons. If you find a reproducible difference, send the date, local time, historical offset, coordinates and the comparison method to Kerala Jyothisham, without sharing personal details you do not want to disclose.