{"id":"vidhyamitra:city-day:perth:1981-09-18:en","page_class":"VM-CD-city-day","url":"https://vidhyamitra.com/city/perth/1981-09-18","language":{"target_lang":"en","base_lang":"en","quality_tier":"canonical"},"data":{"date":"1981-09-18","date_display":"September 18, 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":9,"day":18,"hour":6,"minute":30,"second":0,"calendar":"gregorian"},"julian_day":2444865.770833,"kali_year":5083,"ahargana":1856400.2708,"sun":{"sidereal_longitude":150.7595,"rashi":6,"rashi_name":"Kanyā"},"moon":{"sidereal_longitude":21.3068,"rashi":1,"rashi_name":"Meṣa"},"tithi":{"number":20,"name":"Pañcamī","paksha":"Kṛṣṇa","full_name":"Kṛṣṇa Pañcamī","elongation_degrees":230.5473,"elapsed_within_tithi_degrees":2.5473},"nakshatra":{"number":2,"name":"Bharaṇī","pada":3,"moon_longitude":21.3068,"elapsed_within_degrees":7.9735},"yoga":{"number":13,"name":"Vyāghāta","sum_longitude":172.0663},"karana":{"half_tithi_index":38,"name":"Kaulava"},"vara":{"number":0,"name":"Śukravāra (Friday)"}},"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":9,"day":18,"hour":6,"minute":30,"calendar":"gregorian"},"julian_day":2444865.770833,"ahargana":1856400.2708,"kali_year":5083,"ayanamsa_lahiri":23.5975,"grahas":{"sun":{"sidereal_longitude":151.448106,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":12,"name":"Uttara Phalgunī","pada":2},"retrograde":false},"moon":{"sidereal_longitude":24.311706000000015,"rashi":{"number":1,"name":"Meṣa"},"nakshatra":{"number":2,"name":"Bharaṇī","pada":4},"retrograde":false,"latitude":-4.3961},"mars":{"sidereal_longitude":106.69640600000002,"rashi":{"number":4,"name":"Karka"},"nakshatra":{"number":9,"name":"Aśleṣā","pada":1},"retrograde":false},"mercury":{"sidereal_longitude":177.31030599999997,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":14,"name":"Citrā","pada":2},"retrograde":false},"jupiter":{"sidereal_longitude":171.879006,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":13,"name":"Hasta","pada":4},"retrograde":false},"venus":{"sidereal_longitude":192.60840600000006,"rashi":{"number":7,"name":"Tulā"},"nakshatra":{"number":15,"name":"Svātī","pada":2},"retrograde":false},"saturn":{"sidereal_longitude":166.72120599999994,"rashi":{"number":6,"name":"Kanyā"},"nakshatra":{"number":13,"name":"Hasta","pada":3},"retrograde":false},"rahu":{"sidereal_longitude":98.98,"rashi":{"number":4,"name":"Karka"},"nakshatra":{"number":8,"name":"Puṣya","pada":2},"retrograde":false},"ketu":{"sidereal_longitude":278.98,"rashi":{"number":10,"name":"Makara"},"nakshatra":{"number":21,"name":"Uttara Āṣāḍhā","pada":4},"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":9,"day":18,"hour":6,"minute":30,"second":0,"calendar":"gregorian"},"julian_day":2444865.770833,"kali_year":5083,"ahargana":1856400.2708,"sun":{"sidereal_longitude":150.7595,"rashi":6,"rashi_name":"Kanyā"},"moon":{"sidereal_longitude":21.3068,"rashi":1,"rashi_name":"Meṣa"},"tithi":{"number":20,"name":"Pañcamī","paksha":"Kṛṣṇa","full_name":"Kṛṣṇa Pañcamī","elongation_degrees":230.5473,"elapsed_within_tithi_degrees":2.5473},"nakshatra":{"number":2,"name":"Bharaṇī","pada":3,"moon_longitude":21.3068,"elapsed_within_degrees":7.9735},"yoga":{"number":13,"name":"Vyāghāta","sum_longitude":172.0663},"karana":{"half_tithi_index":38,"name":"Kaulava"},"vara":{"number":0,"name":"Śukravāra (Friday)"}},"eclipse_current":{"solar":{"type":"solar","occurs":false,"moon_latitude":-4.396,"elongation":129.453},"lunar":{"type":"lunar","occurs":false,"moon_latitude":-4.396,"opposition_distance":50.547}},"eclipse_window_40days":[]},"city":{"slug":"perth","name":"Perth, Australia","lat":-31.9505,"lon":115.8605,"tz_offset_hours":8,"country":"AU","tier":"diaspora"},"tier2":{"city":{"slug":"perth","name":"Perth, Australia","lat":-31.9505,"lon":115.8605,"tz_offset_hours":8,"country":"AU","tier":"diaspora"},"sunriseLocal":"06:11","sunsetLocal":"18:09","solarNoonLocal":"12:10","dayLengthHours":11.96721636377093,"dayLengthDisplay":"11 Hours 58 Mins 02 Secs","nightLengthDisplay":"12 Hours 01 Mins 58 Secs","moonriseLocal":"22:23","moonsetLocal":"09:00","rahuKala":{"name":"Rāhu Kāla","start":"10:40","end":"12:10","startHours":10.669897584967394,"endHours":12.165799630438759,"quality":"inauspicious"},"yamaganda":{"name":"Yamaganda","start":"15:09","end":"16:39","startHours":15.157603721381491,"endHours":16.65350576685286,"quality":"inauspicious"},"gulika":{"name":"Gulika Kāla","start":"07:41","end":"09:10","startHours":7.678093494024661,"endHours":9.173995539496026,"quality":"inauspicious"},"durMuhurta":[{"name":"Dur Muhūrta","start":"08:58","end":"09:22","startHours":8.974541933433178,"endHours":9.373449145558876,"quality":"avoid"}],"varjyam":{"name":"Varjyam","start":"06:41","end":"07:00","startHours":6.680825463710416,"endHours":6.999951233410974,"quality":"avoid"},"abhijit":{"name":"Abhijit Muhūrta","start":"11:46","end":"12:34","startHours":11.766892418313061,"endHours":12.564706842564457,"quality":"auspicious"},"brahmaMuhurta":{"name":"Brahma Muhūrta","start":"04:35","end":"05:23","startHours":4.586562600050504,"endHours":5.384377024301899,"quality":"auspicious"},"pratahSandhya":{"name":"Prātaḥ Sandhyā","start":"05:11","end":"06:11","startHours":5.18492341823905,"endHours":6.1821914485532945,"quality":"auspicious"},"vijayaMuhurta":{"name":"Vijaya Muhūrta","start":"14:10","end":"14:57","startHours":14.16033569106725,"endHours":14.958150115318645,"quality":"auspicious"},"godhuliMuhurta":{"name":"Godhūli Muhūrta","start":"17:57","end":"18:21","startHours":17.949407812324225,"endHours":18.349407812324223,"quality":"auspicious"},"sayahnaSandhya":{"name":"Sāyāhna Sandhyā","start":"18:09","end":"18:39","startHours":18.149407812324224,"endHours":18.648041827481347,"quality":"auspicious"},"amritKala":{"name":"Amṛta Kāla","start":"17:54","end":"19:39","startHours":17.899407812324224,"endHours":19.649407812324224,"quality":"auspicious"},"nishitaMuhurta":{"name":"Niśīta Muhūrta","start":"23:46","end":"00:34","startHours":23.766892418313063,"endHours":24.564706842564455,"quality":"auspicious"},"dayChoghadiyas":[{"name":"Chala","start":"06:11","end":"07:41","startHours":6.1821914485532945,"endHours":7.678093494024661,"quality":"neutral"},{"name":"Labha","start":"07:41","end":"09:10","startHours":7.678093494024661,"endHours":9.173995539496026,"quality":"auspicious"},{"name":"Amṛta","start":"09:10","end":"10:40","startHours":9.173995539496026,"endHours":10.669897584967394,"quality":"auspicious"},{"name":"Kāla","start":"10:40","end":"12:10","startHours":10.669897584967394,"endHours":12.165799630438759,"quality":"inauspicious"},{"name":"Śubha","start":"12:10","end":"13:40","startHours":12.165799630438759,"endHours":13.661701675910127,"quality":"auspicious"},{"name":"Roga","start":"13:40","end":"15:09","startHours":13.661701675910127,"endHours":15.157603721381491,"quality":"inauspicious"},{"name":"Udveg","start":"15:09","end":"16:39","startHours":15.157603721381491,"endHours":16.65350576685286,"quality":"inauspicious"},{"name":"Chala","start":"16:39","end":"18:09","startHours":16.65350576685286,"endHours":18.149407812324224,"quality":"neutral"}],"nightChoghadiyas":[{"name":"Roga","start":"18:09","end":"19:39","startHours":18.149407812324224,"endHours":19.65350576685286,"quality":"inauspicious"},{"name":"Udveg","start":"19:39","end":"21:09","startHours":19.65350576685286,"endHours":21.15760372138149,"quality":"inauspicious"},{"name":"Chala","start":"21:09","end":"22:40","startHours":21.15760372138149,"endHours":22.661701675910123,"quality":"neutral"},{"name":"Labha","start":"22:40","end":"00:10","startHours":22.661701675910123,"endHours":24.16579963043876,"quality":"auspicious"},{"name":"Amṛta","start":"00:10","end":"01:40","startHours":24.16579963043876,"endHours":25.669897584967394,"quality":"auspicious"},{"name":"Kāla","start":"01:40","end":"03:10","startHours":25.669897584967394,"endHours":27.173995539496026,"quality":"inauspicious"},{"name":"Śubha","start":"03:10","end":"04:41","startHours":27.173995539496026,"endHours":28.678093494024658,"quality":"auspicious"},{"name":"Roga","start":"04:41","end":"06:11","startHours":28.678093494024658,"endHours":30.182191448553294,"quality":"inauspicious"}],"horas":[{"name":"Hora 1","start":"06:11","end":"07:11","startHours":6.1821914485532945,"endHours":7.1821914485532945,"planetary_lord":"Venus"},{"name":"Hora 2","start":"07:11","end":"08:11","startHours":7.1821914485532945,"endHours":8.182191448553294,"planetary_lord":"Sun"},{"name":"Hora 3","start":"08:11","end":"09:11","startHours":8.182191448553294,"endHours":9.182191448553294,"planetary_lord":"Mars"},{"name":"Hora 4","start":"09:11","end":"10:11","startHours":9.182191448553294,"endHours":10.182191448553294,"planetary_lord":"Jupiter"},{"name":"Hora 5","start":"10:11","end":"11:11","startHours":10.182191448553294,"endHours":11.182191448553294,"planetary_lord":"Saturn"},{"name":"Hora 6","start":"11:11","end":"12:11","startHours":11.182191448553294,"endHours":12.182191448553294,"planetary_lord":"Moon"},{"name":"Hora 7","start":"12:11","end":"13:11","startHours":12.182191448553294,"endHours":13.182191448553294,"planetary_lord":"Mercury"},{"name":"Hora 8","start":"13:11","end":"14:11","startHours":13.182191448553294,"endHours":14.182191448553294,"planetary_lord":"Venus"},{"name":"Hora 9","start":"14:11","end":"15:11","startHours":14.182191448553294,"endHours":15.182191448553294,"planetary_lord":"Sun"},{"name":"Hora 10","start":"15:11","end":"16:11","startHours":15.182191448553294,"endHours":16.182191448553294,"planetary_lord":"Mars"},{"name":"Hora 11","start":"16:11","end":"17:11","startHours":16.182191448553294,"endHours":17.182191448553294,"planetary_lord":"Jupiter"},{"name":"Hora 12","start":"17:11","end":"18:11","startHours":17.182191448553294,"endHours":18.182191448553294,"planetary_lord":"Saturn"},{"name":"Hora 13","start":"18:11","end":"19:11","startHours":18.182191448553294,"endHours":19.182191448553294,"planetary_lord":"Moon"},{"name":"Hora 14","start":"19:11","end":"20:11","startHours":19.182191448553294,"endHours":20.182191448553294,"planetary_lord":"Mercury"},{"name":"Hora 15","start":"20:11","end":"21:11","startHours":20.182191448553294,"endHours":21.182191448553294,"planetary_lord":"Venus"},{"name":"Hora 16","start":"21:11","end":"22:11","startHours":21.182191448553294,"endHours":22.182191448553294,"planetary_lord":"Sun"},{"name":"Hora 17","start":"22:11","end":"23:11","startHours":22.182191448553294,"endHours":23.182191448553294,"planetary_lord":"Mars"},{"name":"Hora 18","start":"23:11","end":"00:11","startHours":23.182191448553294,"endHours":24.182191448553294,"planetary_lord":"Jupiter"},{"name":"Hora 19","start":"00:11","end":"01:11","startHours":24.182191448553294,"endHours":25.182191448553294,"planetary_lord":"Saturn"},{"name":"Hora 20","start":"01:11","end":"02:11","startHours":25.182191448553294,"endHours":26.182191448553294,"planetary_lord":"Moon"},{"name":"Hora 21","start":"02:11","end":"03:11","startHours":26.182191448553294,"endHours":27.182191448553294,"planetary_lord":"Mercury"},{"name":"Hora 22","start":"03:11","end":"04:11","startHours":27.182191448553294,"endHours":28.182191448553294,"planetary_lord":"Venus"},{"name":"Hora 23","start":"04:11","end":"05:11","startHours":28.182191448553294,"endHours":29.182191448553294,"planetary_lord":"Sun"},{"name":"Hora 24","start":"05:11","end":"06:11","startHours":29.182191448553294,"endHours":30.182191448553294,"planetary_lord":"Mars"}],"taraBala":{"favorable_nakshatras":["Kṛttikā","Rohiṇī","Mṛgaśirā","Ārdrā","Punarvasu","Uttara Phalgunī","Hasta","Citrā","Svātī","Viśākhā","Uttara Āṣāḍhā","Śravaṇa","Dhaniṣṭhā","Śatabhiṣaj","Pūrva Bhādrapadā"],"unfavorable_nakshatras":["Aśvinī","Bharaṇī","Puṣya","Aśleṣā","Maghā","Pūrva Phalgunī","Anurādhā","Jyeṣṭhā","Mūla","Pūrva Āṣāḍhā","Uttara Bhādrapadā","Revatī"],"nature":"Janma-tara if same nakshatra; favorable for 15 nakshatras"},"chandraBala":{"favorable_rashis":["Meṣa","Mithuna","Kanyā","Tulā","Makara","Kumbha"],"unfavorable_rashis":["Vṛṣabha","Karka","Siṃha","Vṛścika","Dhanu","Mīna"]},"dishaShool":"West (Paścim)","chandraVasa":"East","rahuVasa":"South-East","anandadiYoga":{"name":"Mausala","quality":"Inauspicious"},"drikRitu":"Varṣā (Monsoon)","vedicRitu":"Varṣā (Monsoon)","drikAyana":"Dakṣiṇāyana","vedicAyana":"Dakṣiṇāyana","meta":{"method":"BOB-History Sūrya-Siddhānta + Vidhyamitra Tier-2 spherical localization (Drikpanchang-parity)","declination":1.968455806324778,"eotMinutes":6.610022173674397,"ayanamsa":23.5975}},"calendars":{"vikram_samvat":2038,"vikram_samvatsara":"Bhāva","saka_samvat":1903,"saka_samvatsara":"Durmati","bengali_samvat":1388,"malayalam_era":1157,"nanakshahi_year":512,"lunar_month":"Āśvina","lunar_month_paksha_full":"Āśvina Kṛṣṇa Pakṣa","solar_month":"Kanyā (Puraṭṭāsi)","ritu":"Śarad (Autumn)","display_summary":"Āśvina Kṛṣṇa Pañcamī · Vikram 2038 Bhāva · Śaka 1903 Durmati"},"festivals":[{"id":"kanya-sankranti","name":"Kanyā Saṅkrānti (Mahālaya begins)","name_sanskrit":"कन्या सङ्क्रान्ति","tradition":"Pan-Hindu","significance":"Sun enters Virgo; Mahālaya / Pitṛ-Pakṣa solar marker.","vrata":false,"detection":{"sun_rashi":"Kanyā"},"precedence":4}],"todays_walk":{"walk":{"id":"shukra-walk","name":"Śukra Walk","name_sanskrit":"शुक्र यात्रा","type":"graha","description":"Beauty + creativity in dharma + BG 10.36.","step_count":5,"url":"/walk/shukra-walk"},"reason":"Śukravāra (Friday) — its presiding graha's walk."},"cosmic_resonances":[]},"validity":{"eternal":false,"location_specific":"perth"},"liturgical":{"opening":"जय श्री कृष्ण","closing":"ॐ तत् सत्","attribution":"Computed by Vidhyamitra Sūrya-Siddhānta substrate + Vidhyamitra Tier-2 layer"},"seo":{"title":"Pañchāṅga September 18, 1981 CE · Perth, Australia · Vidhyamitra","description":"September 18, 1981 CE for Perth, Australia: Kṛṣṇa Pañcamī, sūryodaya 06:11, sūryāsta 18:09.","schema_org_type":"Article","canonical":"https://vidhyamitra.com/city/perth/1981-09-18","hreflang_alternates":{"en":"https://vidhyamitra.com/city/perth/1981-09-18","sa":"https://sa.vidhyamitra.com/city/perth/1981-09-18","hi":"https://hi.vidhyamitra.com/city/perth/1981-09-18","x-default":"https://vidhyamitra.com/city/perth/1981-09-18"}},"provenance":[{"pillar":"BOB-History","pillar_version":"2.12.0","method":"Sūrya-Siddhānta first-principles + Bhāskara II + Kerala-school (Mādhava-Nīlakaṇṭha) corrections","retrieved_at":"2026-05-18T23:34:32.807Z","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":"2026-05-18T23:34:32.807Z","verification":{"type":"community-validated","markers":["matches Drikpanchang ±1 minute on Narasiṁha Jayantī 2026"],"confidence":"verified"}}],"meta":{"generated_at":"2026-05-18T23:34:32.807Z","pillar_versions":{"Sūrya-Siddhānta":"Pūrṇa","Vidhyamitra-Tier2":"Pūrṇa"}}}