सिद्धान्त-पञ्चाङ्ग · Siddhānta Pañcāṅga

१ · स्थान · दिन — place and day

The position stays on this device: the page sends nothing anywhere (your browser finds the position itself). The UTC offset is fixed; enter a summer-time offset yourself.

Clock times: the instant the engine gives, less the meridian's longitude (÷ 360 of a day), plus your UTC offset. The Sūrya-Siddhānta's civil day is a turn of the Earth, sunrise to sunrise, so no ΔT enters. Beside each time is its count from sunrise in ghaṭī (घ) and vināḍī (वि) of the star-wheel's turn (SS 1.11-1.12), as the engine returns it.

२ · आज का पञ्चाङ्ग — the day's pañcāṅga

३ · काल-खण्ड — the parts of the day

४ · मास — the month, day by day

Each day shows the tithi and nakṣatra at its sunrise. A tithi that begins and ends between two sunrises is marked kṣaya; one that runs through two sunrises, vṛddhi. Choose a day to see its pañcāṅga.

५ · वर्ष के उत्सव — the year's festivals, saṅkrāntis and ayanas

६ · ग्रहण — eclipses in the next 400 days

The text's eclipses at this place (SS chapters 4, 5 and 6.13), from the chosen day: this is the text's eclipse, not the sky's, until the vedha says how far apart they are.

सूर्य-ग्रहण को कभी भी नंगी आँखों, धूप के चश्मे या कैमरे से सीधे न देखें; केवल प्रमाणित सौर-फ़िल्टर या पिनहोल-प्रक्षेपण से। · Never look at a solar eclipse with the naked eye, sunglasses or through a camera; use only a certified solar filter or pinhole projection. The text's magnitude is the text's prediction, not a safety guide.

७ · विंशोत्तरी दशा — Vimśottarī daśā

Only the birth instant matters: the Moon's nakṣatra then. The place gives the clock's UTC offset (enter the offset in force at the birth, summer time included); its latitude and longitude are not used. Birth details are not stored.

८ · परिचय — about these numbers

• These are the Sūrya-Siddhānta's numbers: its own revolutions, true Sun and Moon (chapter 2, with Mādhava's sine), ayanāṃśa (3.9-3.10) and eclipse rules (chapters 4-6). They are computed on your device by the engine's files, and nothing is fetched.
• They are not yet checked against the sky. Observations are what correct them: that is the work of the observation companion, वेध · vedha.
• Printed pañcāṅgas use other models and other ayanāṃśas, so a tithi's end can differ by hours, and a festival or a saṅkrānti can fall a day apart.
• Festival rules (which tithi, in which part of the day, which of two days) are simplified common practice and are marked unverified, unless a row is marked as from the text: there is no Rohiṇī check for Janmāṣṭamī and no daśamī-vedha for Ekādaśī. The names of most yogas, of the movable karaṇas after Bava and of the tithis are the standard lists; no text in this repository states them.

मान्यताएँ · conventions

• Months come from the engine as amānta (new moon to new moon), named by the saṅkrānti in them. The pūrṇimānta name is derived on this page — the dark half takes the next month's name, and an adhika month stays adhika — and is labelled common practice.
• The karaṇas around amāvāsyā follow SS 2.67's order: Śakuni, Nāga, Catuṣpada, Kiṃstughna (Nāga before Catuṣpada; the later common order differs).
• panchanga.js does not flag kṣaya or vṛddhi tithis. The month grid derives them by comparing the tithis at two sunrises.
• The daśā year is the Sūrya-Siddhānta's solar year, 365.2587565 civil days (SS 14.10 with 1.37), and the balance at birth is by the time gone in the birth nakṣatra (BPHS 46.16); the other choices dasha.js offers are in the form.
• Clock times use 75.7885° E for Ujjain's meridian, its modern position, not a figure from the text.