Method
Calculation method and sources
What StarScore measures, which coordinate system each result uses, and where approximation enters.
Ephemeris source
Planetary longitudes, retrograde motion, rise and set times, 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 positions | 0° Aries is anchored to the March equinox. |
|---|---|
| Vedic positions | Sidereal zodiac with Lahiri (Chitrapaksha) ayanamsa. Rahu is the mean lunar node; Ketu is opposite. |
| Natal houses (Western) | Placidus with a supplied birth time and supported location. If Placidus is unavailable, no alternative houses or angles are substituted. |
| Kundli houses | Whole sign from an available sidereal lagna. Without it, the D1 diagram uses an explicitly labelled Moon reference and supplies no natal house numbers. |
| Navamsa | Standard D9: nine parts of 3°20′ per sign, starting from the sign itself for movable signs, the ninth for fixed signs and the fifth for dual signs. D9 houses, lagna and the house diagram are omitted when the natal angles are unavailable. |
| Daily sign readings | Tropical Sun-sign readings using whole-sign solar houses. Sky sampled at 12:00 UTC. These are separate from traditional sidereal Moon-rashi readings. |
City mode uses an IANA timezone to resolve the offset in force at the supplied local birth date and time, including historical daylight saving. The result displays the resolved timezone, offset and UTC instant. A repeated clock requests a choice between valid offsets; a skipped clock requests correction or an explicit recorded offset. Manual mode makes that chosen offset authoritative and identifies it as an override. City coordinates are approximate town locations, not independently verified birth addresses.
Aspects and prediction windows
The transit engine uses conjunction, square, trine and opposition within 6°, and sextile within 4°. Daily sky panels display a tighter 3° subset. Weekly and monthly readings keep the tightest instance of each planet-pair aspect inside the window and exclude the Moon. The engine samples at noon UTC each day, so a reported date is the closest daily sample, not an exact aspect time.
Panchang
City event searches use the actual interval between consecutive local midnights. A daylight-saving change can make that civil date 23 or 25 hours long. Moonrise and moonset are included only when their instants fall inside that date, and each displayed event uses the timezone offset at its own instant. Fixed-offset API requests retain a 24-hour civil-day interval.
City panchang pages are sunrise based. Sunrise and sunset use the Sun's upper limb with standard refraction at sea level for the city's coordinates; moonrise and moonset use the disc centre without refraction, which reproduces the common Indian panchang sources to the minute. Tithi is the Moon's elongation from the Sun in 12° steps, nakshatra the sidereal Moon in 13°20′ steps, yoga the sidereal Sun plus Moon in the same steps and karana the half tithi. Each limb is read at sunrise and the instant it ends is found by bisection on the ephemeris to better than a second, then shown to the minute; limbs that end before the next sunrise are listed in order. Rahu kaal, Gulika kaal and Yamaganda are eighths of the daylight arc by weekday; Abhijit is the eighth of fifteen daylight muhurtas and is omitted on Wednesdays. Lunar months follow the amanta reckoning, named by the Sun's sidereal sign at the preceding new moon, with the purnimanta name alongside; an adhika month is flagged when two new moons fall in one sign. Vikram Samvat counts from Chaitra; Shaka Samvat is 135 less.
Kundli matching
Ashtakoot uses the two sidereal Moon longitudes. Varna follows the rashi classes (water signs Brahmin, fire Kshatriya, earth Vaishya, air Shudra). Vashya uses the sign classes human, quadruped, water, wild and insect with a group table. Tara counts nakshatras both ways in nines, losing 1.5 for remainders 3, 5 and 7. Yoni uses the classical 14-animal table. Graha maitri uses natural friendship between the sign lords (mutual friends 5, friend and neutral 4, both neutral 3, friend and enemy 1, neutral and enemy 0.5, mutual enemies 0). Gana scores same 6, deva with manushya 6 or 5 by direction, deva with rakshasa 1, manushya with rakshasa 0. Bhakoot scores 7 unless the signs are 2/12, 5/9 or 6/8 apart. Nadi scores 8 for different nadis. Manglik is Mars in houses 1, 2, 4, 7, 8 or 12 counted whole sign from the lagna and from the Moon. Classical exceptions and cancellations are described on the page but not applied automatically.
Vimshottari
The sidereal Moon is divided into 27 nakshatras of 13°20′ and four padas of 3°20′. Dashas use the Moon's progress through its nakshatra to set the remaining first period, then follow the fixed 120-year sequence with one year as 365.25 days. Dates are calendar-day approximations. Starts are inclusive and ends exclusive; individually truncated subperiods can leave a short gap before their parent period ends. The result states the date used to identify the active periods.
Coordinates versus interpretation
Planet positions, angles, padas, panchang timings, guna scores and period dates are computed outputs. Compatibility language, nakshatra and mahadasha themes and the readings attached to aspects are traditional Jyotisha or astrological interpretation; they are labelled as such and should not be read as empirical facts.