starscore Calculate chartChart

Calculation method and sources

What StarScore measures, which coordinate system each result uses, and where approximation enters.

Ephemeris source

Planetary longitudes, retrograde motion, house cusps and angles are computed with Swiss Ephemeris through its Python bindings. The upstream model and API are documented in the official Swiss Ephemeris manual and programmer's manual. StarScore does not substitute a lookup table or a language model for these coordinates.

Zodiacs, houses and time

Tropical positions0° Aries is anchored to the March equinox.
Vedic positionsSidereal zodiac with Lahiri ayanamsa.
Natal housesPlacidus, only when birth time and place are supplied.
Daily sign readingsWhole-sign solar houses, because no personal birth time is known.
Daily sky timestamp12:00 UTC on the displayed date.

Birth times are converted to UTC with the offset selected in the form. The city picker supplies modern coordinates and a suggested offset; historical daylight-saving changes still require the user to verify the offset in force on the birth date.

Aspects and prediction windows

The natal transit engine uses conjunction, square, trine and opposition within 6°, and sextile within 4°. Daily sky panels display a tighter 3° subset so the page foregrounds current geometry rather than every background aspect. Candidate transits are ranked by planet weight and closeness to exactness. The engine samples at noon UTC each day, so a reported transit date is the closest daily sample, not an exact aspect time.

Vedic calculations

The sidereal Moon is divided into 27 nakshatras of 13°20′ and four padas of 3°20′. Vimshottari dashas use the Moon's progress through its nakshatra to set the remaining first period, then follow the fixed 120-year sequence. One year is represented as 365.25 days.

Panchang and calendar limits

The current Panchang page is a noon-UTC snapshot, not a location-specific Muhurta calendar. It publishes Vara, Tithi, Nakshatra and Yoga but does not yet calculate local sunrise, Karana, transition times or Rahu Kalam. Retrograde calendars estimate the UTC station day by comparing apparent longitude in successive noon-UTC samples.

Coordinates versus interpretation

Planet positions, angles, padas and period dates are computed outputs. Compatibility language and nakshatra or mahadasha themes are labelled as traditional Jyotisha or astrological interpretation; they are not measurements produced by Swiss Ephemeris and should not be read as empirical facts.

A computed chart can be precise while its interpretation remains a symbolic framework. StarScore exposes the inputs and keeps prediction outcomes public so the two are not confused.