{"id":"vidhyamitra:city-day:phoenix:1981-12-20:en","page_class":"VM-CD-city-day","url":"https://vidhyamitra.com/city/phoenix/1981-12-20","language":{"target_lang":"en","base_lang":"en","quality_tier":"canonical"},"data":{"date":"1981-12-20","date_display":"December 20, 1981 CE","panchanga":{"method":"Sūrya Siddhānta + Bhāskara-II iterative manda + Kerala-school (Mādhava-Nīlakaṇṭha) evection + variation + annual equation","engine_version":"2.0 (Kerala-school enhanced)","accuracy_note":"Sub-degree on Moon at any Kali-Yuga date (~2-5° residual max)","tradition_chain":"Āryabhaṭa(499) → Brahmagupta(628) → Bhāskara II(1150) → Mādhava(~1400) → Parameśvara(1430) → Nīlakaṇṭha(1501) → this","input":{"year":1981,"month":12,"day":20,"hour":6,"minute":30,"second":0,"calendar":"gregorian"},"julian_day":2444958.770833,"kali_year":5083,"ahargana":1856493.2708,"sun":{"sidereal_longitude":244.1697,"rashi":9,"rashi_name":"Dhanu"},"moon":{"sidereal_longitude":171.9197,"rashi":6,"rashi_name":"Kanyā"},"tithi":{"number":24,"name":"Navamī","paksha":"Kṛṣṇa","full_name":"Kṛṣṇa Navamī","elongation_degrees":287.75,"elapsed_within_tithi_degrees":11.75},"nakshatra":{"number":13,"name":"Hasta","pada":4,"moon_longitude":171.9197,"elapsed_within_degrees":11.9197},"yoga":{"number":5,"name":"Śobhana","sum_longitude":56.0894},"karana":{"half_tithi_index":47,"name":"Gara"},"vara":{"number":2,"name":"Ravivāra (Sunday)"}},"sky":{"method":"Sūrya-Siddhāntic Bhāskara-II 4-step iteration with atan2-based śīghra + varying peripheries + lunar latitude","engine_version":"3.0 (Pūrṇa — complete SS implementation)","tradition_sources":"Āryabhaṭīya 499 CE → SS Ch.1-5 Burgess 1860 → Siddhānta-Śiromaṇi Bhāskara II 1150 → Tantrasaṅgraha Nīlakaṇṭha 1501","input":{"year":1981,"month":12,"day":20,"hour":6,"minute":30,"calendar":"gregorian"},"julian_day":2444958.770833,"ahargana":1856493.2708,"kali_year":5083,"ayanamsa_lahiri":23.6011,"grahas":{"sun":{"sidereal_longitude":244.46675299999993,"rashi":{"number":9,"name":"Dhanu"},"nakshatra":{"number":19,"name":"Mūla","pada":2},"retrograde":false},"moon":{"sidereal_longitude":175.067453,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":14,"name":"Citrā","pada":1},"retrograde":false,"latitude":4.3993},"mars":{"sidereal_longitude":158.483653,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":12,"name":"Uttara Phalgunī","pada":4},"retrograde":false},"mercury":{"sidereal_longitude":250.04015300000003,"rashi":{"number":9,"name":"Dhanu"},"nakshatra":{"number":19,"name":"Mūla","pada":4},"retrograde":false},"jupiter":{"sidereal_longitude":191.01335300000005,"rashi":{"number":7,"name":"Tulā"},"nakshatra":{"number":15,"name":"Svātī","pada":2},"retrograde":false},"venus":{"sidereal_longitude":282.946953,"rashi":{"number":10,"name":"Makara"},"nakshatra":{"number":22,"name":"Śravaṇa","pada":1},"retrograde":true},"saturn":{"sidereal_longitude":176.81935299999998,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":14,"name":"Citrā","pada":2},"retrograde":false},"rahu":{"sidereal_longitude":94.0524,"rashi":{"number":4,"name":"Karka"},"nakshatra":{"number":8,"name":"Puṣya","pada":1},"retrograde":false},"ketu":{"sidereal_longitude":274.0524,"rashi":{"number":10,"name":"Makara"},"nakshatra":{"number":21,"name":"Uttara Āṣāḍhā","pada":3},"retrograde":false}},"panchang":{"method":"Sūrya Siddhānta + Bhāskara-II iterative manda + Kerala-school (Mādhava-Nīlakaṇṭha) evection + variation + annual equation","engine_version":"2.0 (Kerala-school enhanced)","accuracy_note":"Sub-degree on Moon at any Kali-Yuga date (~2-5° residual max)","tradition_chain":"Āryabhaṭa(499) → Brahmagupta(628) → Bhāskara II(1150) → Mādhava(~1400) → Parameśvara(1430) → Nīlakaṇṭha(1501) → this","input":{"year":1981,"month":12,"day":20,"hour":6,"minute":30,"second":0,"calendar":"gregorian"},"julian_day":2444958.770833,"kali_year":5083,"ahargana":1856493.2708,"sun":{"sidereal_longitude":244.1697,"rashi":9,"rashi_name":"Dhanu"},"moon":{"sidereal_longitude":171.9197,"rashi":6,"rashi_name":"Kanyā"},"tithi":{"number":24,"name":"Navamī","paksha":"Kṛṣṇa","full_name":"Kṛṣṇa Navamī","elongation_degrees":287.75,"elapsed_within_tithi_degrees":11.75},"nakshatra":{"number":13,"name":"Hasta","pada":4,"moon_longitude":171.9197,"elapsed_within_degrees":11.9197},"yoga":{"number":5,"name":"Śobhana","sum_longitude":56.0894},"karana":{"half_tithi_index":47,"name":"Gara"},"vara":{"number":2,"name":"Ravivāra (Sunday)"}},"eclipse_current":{"solar":{"type":"solar","occurs":false,"moon_latitude":4.399,"elongation":72.25},"lunar":{"type":"lunar","occurs":false,"moon_latitude":4.399,"opposition_distance":107.75}},"eclipse_window_40days":[]},"city":{"slug":"phoenix","name":"Phoenix, USA","lat":33.4484,"lon":-112.074,"tz_offset_hours":-7,"country":"US","tier":"diaspora"},"tier2":{"city":{"slug":"phoenix","name":"Phoenix, USA","lat":33.4484,"lon":-112.074,"tz_offset_hours":-7,"country":"US","tier":"diaspora"},"sunriseLocal":"07:28","sunsetLocal":"17:24","solarNoonLocal":"12:26","dayLengthHours":9.933785660152061,"dayLengthDisplay":"9 Hours 56 Mins 02 Secs","nightLengthDisplay":"14 Hours 03 Mins 58 Secs","moonriseLocal":"02:05","moonsetLocal":"13:32","rahuKala":{"name":"Rāhu Kāla","start":"16:10","end":"17:24","startHours":16.165904330515875,"endHours":17.407627538034884,"quality":"inauspicious"},"yamaganda":{"name":"Yamaganda","start":"12:26","end":"13:41","startHours":12.440734707958853,"endHours":13.682457915477862,"quality":"inauspicious"},"gulika":{"name":"Gulika Kāla","start":"14:55","end":"16:10","startHours":14.924181122996869,"endHours":16.165904330515875,"quality":"inauspicious"},"durMuhurta":[{"name":"Dur Muhūrta","start":"09:48","end":"10:07","startHours":9.79172519858497,"endHours":10.122851387256706,"quality":"avoid"}],"varjyam":{"name":"Varjyam","start":"07:53","end":"08:09","startHours":7.887749613722492,"endHours":8.15265056465988,"quality":"avoid"},"abhijit":{"name":"Abhijit Muhūrta","start":"12:07","end":"12:46","startHours":12.109608519287118,"endHours":12.771860896630589,"quality":"auspicious"},"brahmaMuhurta":{"name":"Brahma Muhūrta","start":"06:09","end":"06:49","startHours":6.149337123195881,"endHours":6.811589500539352,"quality":"auspicious"},"pratahSandhya":{"name":"Prātaḥ Sandhyā","start":"06:39","end":"07:28","startHours":6.646026406203484,"endHours":7.473841877882823,"quality":"auspicious"},"vijayaMuhurta":{"name":"Vijaya Muhūrta","start":"14:06","end":"14:46","startHours":14.09636565131753,"endHours":14.758618028661001,"quality":"auspicious"},"godhuliMuhurta":{"name":"Godhūli Muhūrta","start":"17:12","end":"17:36","startHours":17.207627538034885,"endHours":17.607627538034883,"quality":"auspicious"},"sayahnaSandhya":{"name":"Sāyāhna Sandhyā","start":"17:24","end":"17:49","startHours":17.407627538034884,"endHours":17.821535273874552,"quality":"auspicious"},"amritKala":{"name":"Amṛta Kāla","start":"17:09","end":"18:54","startHours":17.157627538034884,"endHours":18.907627538034884,"quality":"auspicious"},"nishitaMuhurta":{"name":"Niśīta Muhūrta","start":"00:07","end":"00:46","startHours":24.109608519287118,"endHours":24.77186089663059,"quality":"auspicious"},"dayChoghadiyas":[{"name":"Udveg","start":"07:28","end":"08:43","startHours":7.473841877882823,"endHours":8.715565085401831,"quality":"inauspicious"},{"name":"Chala","start":"08:43","end":"09:57","startHours":8.715565085401831,"endHours":9.957288292920838,"quality":"neutral"},{"name":"Labha","start":"09:57","end":"11:12","startHours":9.957288292920838,"endHours":11.199011500439845,"quality":"auspicious"},{"name":"Amṛta","start":"11:12","end":"12:26","startHours":11.199011500439845,"endHours":12.440734707958853,"quality":"auspicious"},{"name":"Kāla","start":"12:26","end":"13:41","startHours":12.440734707958853,"endHours":13.682457915477862,"quality":"inauspicious"},{"name":"Śubha","start":"13:41","end":"14:55","startHours":13.682457915477862,"endHours":14.924181122996869,"quality":"auspicious"},{"name":"Roga","start":"14:55","end":"16:10","startHours":14.924181122996869,"endHours":16.165904330515875,"quality":"inauspicious"},{"name":"Udveg","start":"16:10","end":"17:24","startHours":16.165904330515875,"endHours":17.407627538034884,"quality":"inauspicious"}],"nightChoghadiyas":[{"name":"Śubha","start":"17:24","end":"19:10","startHours":17.407627538034884,"endHours":19.165904330515875,"quality":"auspicious"},{"name":"Roga","start":"19:10","end":"20:55","startHours":19.165904330515875,"endHours":20.92418112299687,"quality":"inauspicious"},{"name":"Udveg","start":"20:55","end":"22:41","startHours":20.92418112299687,"endHours":22.682457915477862,"quality":"inauspicious"},{"name":"Chala","start":"22:41","end":"00:26","startHours":22.682457915477862,"endHours":24.440734707958853,"quality":"neutral"},{"name":"Labha","start":"00:26","end":"02:12","startHours":24.440734707958853,"endHours":26.199011500439845,"quality":"auspicious"},{"name":"Amṛta","start":"02:12","end":"03:57","startHours":26.199011500439845,"endHours":27.957288292920836,"quality":"auspicious"},{"name":"Kāla","start":"03:57","end":"05:43","startHours":27.957288292920836,"endHours":29.71556508540183,"quality":"inauspicious"},{"name":"Śubha","start":"05:43","end":"07:28","startHours":29.71556508540183,"endHours":31.473841877882823,"quality":"auspicious"}],"horas":[{"name":"Hora 1","start":"07:28","end":"08:28","startHours":7.473841877882823,"endHours":8.473841877882823,"planetary_lord":"Sun"},{"name":"Hora 2","start":"08:28","end":"09:28","startHours":8.473841877882823,"endHours":9.473841877882823,"planetary_lord":"Mars"},{"name":"Hora 3","start":"09:28","end":"10:28","startHours":9.473841877882823,"endHours":10.473841877882823,"planetary_lord":"Jupiter"},{"name":"Hora 4","start":"10:28","end":"11:28","startHours":10.473841877882823,"endHours":11.473841877882823,"planetary_lord":"Saturn"},{"name":"Hora 5","start":"11:28","end":"12:28","startHours":11.473841877882823,"endHours":12.473841877882823,"planetary_lord":"Moon"},{"name":"Hora 6","start":"12:28","end":"13:28","startHours":12.473841877882823,"endHours":13.473841877882823,"planetary_lord":"Mercury"},{"name":"Hora 7","start":"13:28","end":"14:28","startHours":13.473841877882823,"endHours":14.473841877882823,"planetary_lord":"Venus"},{"name":"Hora 8","start":"14:28","end":"15:28","startHours":14.473841877882823,"endHours":15.473841877882823,"planetary_lord":"Sun"},{"name":"Hora 9","start":"15:28","end":"16:28","startHours":15.473841877882823,"endHours":16.473841877882823,"planetary_lord":"Mars"},{"name":"Hora 10","start":"16:28","end":"17:28","startHours":16.473841877882823,"endHours":17.473841877882823,"planetary_lord":"Jupiter"},{"name":"Hora 11","start":"17:28","end":"18:28","startHours":17.473841877882823,"endHours":18.473841877882823,"planetary_lord":"Saturn"},{"name":"Hora 12","start":"18:28","end":"19:28","startHours":18.473841877882823,"endHours":19.473841877882823,"planetary_lord":"Moon"},{"name":"Hora 13","start":"19:28","end":"20:28","startHours":19.473841877882823,"endHours":20.473841877882823,"planetary_lord":"Mercury"},{"name":"Hora 14","start":"20:28","end":"21:28","startHours":20.473841877882823,"endHours":21.473841877882823,"planetary_lord":"Venus"},{"name":"Hora 15","start":"21:28","end":"22:28","startHours":21.473841877882823,"endHours":22.473841877882823,"planetary_lord":"Sun"},{"name":"Hora 16","start":"22:28","end":"23:28","startHours":22.473841877882823,"endHours":23.473841877882823,"planetary_lord":"Mars"},{"name":"Hora 17","start":"23:28","end":"00:28","startHours":23.473841877882823,"endHours":24.473841877882823,"planetary_lord":"Jupiter"},{"name":"Hora 18","start":"00:28","end":"01:28","startHours":24.473841877882823,"endHours":25.473841877882823,"planetary_lord":"Saturn"},{"name":"Hora 19","start":"01:28","end":"02:28","startHours":25.473841877882823,"endHours":26.473841877882823,"planetary_lord":"Moon"},{"name":"Hora 20","start":"02:28","end":"03:28","startHours":26.473841877882823,"endHours":27.473841877882823,"planetary_lord":"Mercury"},{"name":"Hora 21","start":"03:28","end":"04:28","startHours":27.473841877882823,"endHours":28.473841877882823,"planetary_lord":"Venus"},{"name":"Hora 22","start":"04:28","end":"05:28","startHours":28.473841877882823,"endHours":29.473841877882823,"planetary_lord":"Sun"},{"name":"Hora 23","start":"05:28","end":"06:28","startHours":29.473841877882823,"endHours":30.473841877882823,"planetary_lord":"Mars"},{"name":"Hora 24","start":"06:28","end":"07:28","startHours":30.473841877882823,"endHours":31.473841877882823,"planetary_lord":"Jupiter"}],"taraBala":{"favorable_nakshatras":["Mṛgaśirā","Ārdrā","Punarvasu","Puṣya","Aśleṣā","Citrā","Svātī","Viśākhā","Anurādhā","Jyeṣṭhā","Dhaniṣṭhā","Śatabhiṣaj","Pūrva Bhādrapadā","Uttara Bhādrapadā","Revatī"],"unfavorable_nakshatras":["Aśvinī","Bharaṇī","Kṛttikā","Rohiṇī","Maghā","Pūrva Phalgunī","Uttara Phalgunī","Hasta","Mūla","Pūrva Āṣāḍhā","Uttara Āṣāḍhā","Śravaṇa"],"nature":"Janma-tara if same nakshatra; favorable for 15 nakshatras"},"chandraBala":{"favorable_rashis":["Mithuna","Karka","Kanyā","Vṛścika","Kumbha","Mīna"],"unfavorable_rashis":["Meṣa","Vṛṣabha","Siṃha","Tulā","Dhanu","Makara"]},"dishaShool":"West (Paścim)","chandraVasa":"North-West","rahuVasa":"North-East","anandadiYoga":{"name":"Mānasa","quality":"Auspicious"},"drikRitu":"Hemanta (Pre-winter)","vedicRitu":"Hemanta (Pre-winter)","drikAyana":"Dakṣiṇāyana","vedicAyana":"Dakṣiṇāyana","meta":{"method":"BOB-History Sūrya-Siddhānta + Vidhyamitra Tier-2 spherical localization (Drikpanchang-parity)","declination":-23.422379579331263,"eotMinutes":1.851917522468745,"ayanamsa":23.6011}},"calendars":{"vikram_samvat":2038,"vikram_samvatsara":"Bhāva","saka_samvat":1903,"saka_samvatsara":"Durmati","bengali_samvat":1388,"malayalam_era":1157,"nanakshahi_year":512,"lunar_month":"Pauṣa","lunar_month_paksha_full":"Pauṣa Kṛṣṇa Pakṣa","solar_month":"Dhanus (Mārgaḻi)","ritu":"Hemanta (Pre-winter)","display_summary":"Pauṣa Kṛṣṇa Navamī · Vikram 2038 Bhāva · Śaka 1903 Durmati"},"festivals":[{"id":"lohri","name":"Lohri","name_sanskrit":"लोहड़ी","tradition":"Regional","significance":"Punjab harvest festival; eve of Makara Saṅkrānti. (Approximated as 13/14 January annually; correct via Sun in Dhanu/Makara cusp.)","vrata":false,"detection":{"sun_rashi":"Dhanu"},"precedence":4},{"id":"dhanu-sankranti","name":"Dhanu Saṅkrānti","name_sanskrit":"धनु सङ्क्रान्ति","tradition":"Pan-Hindu","significance":"Sun enters Sagittarius; Dhanu-māsa (Khara-māsa).","vrata":false,"detection":{"sun_rashi":"Dhanu"},"precedence":5}],"todays_walk":{"walk":{"id":"surya-walk","name":"Sūrya Walk","name_sanskrit":"सूर्य यात्रा","type":"graha","description":"Self-illumination + BG 4.1 (Sun-lineage of Gītā transmission).","step_count":6,"url":"/walk/surya-walk"},"reason":"Ravivāra (Sunday) — its presiding graha's walk."},"cosmic_resonances":[]},"validity":{"eternal":false,"location_specific":"phoenix"},"liturgical":{"opening":"जय श्री कृष्ण","closing":"ॐ तत् सत्","attribution":"Computed by Vidhyamitra Sūrya-Siddhānta substrate + Vidhyamitra Tier-2 layer"},"seo":{"title":"Pañchāṅga December 20, 1981 CE · Phoenix, USA · Vidhyamitra","description":"December 20, 1981 CE for Phoenix, USA: Kṛṣṇa Navamī, sūryodaya 07:28, sūryāsta 17:24.","schema_org_type":"Article","canonical":"https://vidhyamitra.com/city/phoenix/1981-12-20","hreflang_alternates":{"en":"https://vidhyamitra.com/city/phoenix/1981-12-20","sa":"https://sa.vidhyamitra.com/city/phoenix/1981-12-20","hi":"https://hi.vidhyamitra.com/city/phoenix/1981-12-20","x-default":"https://vidhyamitra.com/city/phoenix/1981-12-20"}},"provenance":[{"pillar":"BOB-History","pillar_version":"2.12.0","method":"Sūrya-Siddhānta first-principles + Bhāskara II + Kerala-school (Mādhava-Nīlakaṇṭha) corrections","retrieved_at":"2026-05-21T06:26:54.154Z","verification":{"type":"multi-marker","confidence":"canonical"}},{"pillar":"Vidhyamitra-Tier2","pillar_version":"0.1.0","method":"Spherical astronomy + Lahiri ayanamsa + standard solar declination + EoT correction","retrieved_at":"2026-05-21T06:26:54.154Z","verification":{"type":"community-validated","markers":["matches Drikpanchang ±1 minute on Narasiṁha Jayantī 2026"],"confidence":"verified"}}],"meta":{"generated_at":"2026-05-21T06:26:54.154Z","pillar_versions":{"Sūrya-Siddhānta":"Pūrṇa","Vidhyamitra-Tier2":"Pūrṇa"}}}