{"id":"vidhyamitra:city-day:perth:2018-09-13:en","page_class":"VM-CD-city-day","url":"https://vidhyamitra.com/city/perth/2018-09-13","language":{"target_lang":"en","base_lang":"en","quality_tier":"canonical"},"data":{"date":"2018-09-13","date_display":"September 13, 2018 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":2018,"month":9,"day":13,"hour":6,"minute":30,"second":0,"calendar":"gregorian"},"julian_day":2458374.770833,"kali_year":5120,"ahargana":1869909.2708,"sun":{"sidereal_longitude":145.3385,"rashi":5,"rashi_name":"Siṃha"},"moon":{"sidereal_longitude":188.8196,"rashi":7,"rashi_name":"Tulā"},"tithi":{"number":4,"name":"Caturthī","paksha":"Śukla","full_name":"Śukla Caturthī","elongation_degrees":43.481,"elapsed_within_tithi_degrees":7.481},"nakshatra":{"number":15,"name":"Svātī","pada":1,"moon_longitude":188.8196,"elapsed_within_degrees":2.1529},"yoga":{"number":26,"name":"Indra","sum_longitude":334.1581},"karana":{"half_tithi_index":7,"name":"Viṣṭi"},"vara":{"number":6,"name":"Guruvāra (Thursday)"}},"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":2018,"month":9,"day":13,"hour":6,"minute":30,"calendar":"gregorian"},"julian_day":2458374.770833,"ahargana":1869909.2708,"kali_year":5120,"ayanamsa_lahiri":24.1142,"grahas":{"sun":{"sidereal_longitude":146.105863,"rashi":{"number":5,"name":"Siṃha"},"nakshatra":{"number":11,"name":"Pūrva Phalgunī","pada":4},"retrograde":false},"moon":{"sidereal_longitude":189.66996300000005,"rashi":{"number":7,"name":"Tulā"},"nakshatra":{"number":15,"name":"Svātī","pada":1},"retrograde":false,"latitude":4.4868},"mars":{"sidereal_longitude":276.034363,"rashi":{"number":10,"name":"Makara"},"nakshatra":{"number":21,"name":"Uttara Āṣāḍhā","pada":3},"retrograde":false},"mercury":{"sidereal_longitude":138.611563,"rashi":{"number":5,"name":"Siṃha"},"nakshatra":{"number":11,"name":"Pūrva Phalgunī","pada":2},"retrograde":false},"jupiter":{"sidereal_longitude":204.757163,"rashi":{"number":7,"name":"Tulā"},"nakshatra":{"number":16,"name":"Viśākhā","pada":2},"retrograde":false},"venus":{"sidereal_longitude":188.20256300000005,"rashi":{"number":7,"name":"Tulā"},"nakshatra":{"number":15,"name":"Svātī","pada":1},"retrograde":false},"saturn":{"sidereal_longitude":248.35216300000002,"rashi":{"number":9,"name":"Dhanu"},"nakshatra":{"number":19,"name":"Mūla","pada":3},"retrograde":false},"rahu":{"sidereal_longitude":103.2082,"rashi":{"number":4,"name":"Karka"},"nakshatra":{"number":8,"name":"Puṣya","pada":3},"retrograde":false},"ketu":{"sidereal_longitude":283.2082,"rashi":{"number":10,"name":"Makara"},"nakshatra":{"number":22,"name":"Śravaṇa","pada":1},"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":2018,"month":9,"day":13,"hour":6,"minute":30,"second":0,"calendar":"gregorian"},"julian_day":2458374.770833,"kali_year":5120,"ahargana":1869909.2708,"sun":{"sidereal_longitude":145.3385,"rashi":5,"rashi_name":"Siṃha"},"moon":{"sidereal_longitude":188.8196,"rashi":7,"rashi_name":"Tulā"},"tithi":{"number":4,"name":"Caturthī","paksha":"Śukla","full_name":"Śukla Caturthī","elongation_degrees":43.481,"elapsed_within_tithi_degrees":7.481},"nakshatra":{"number":15,"name":"Svātī","pada":1,"moon_longitude":188.8196,"elapsed_within_degrees":2.1529},"yoga":{"number":26,"name":"Indra","sum_longitude":334.1581},"karana":{"half_tithi_index":7,"name":"Viṣṭi"},"vara":{"number":6,"name":"Guruvāra (Thursday)"}},"eclipse_current":{"solar":{"type":"solar","occurs":false,"moon_latitude":4.487,"elongation":43.481},"lunar":{"type":"lunar","occurs":false,"moon_latitude":4.487,"opposition_distance":136.519}},"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":"06:18","sunsetLocal":"18:06","solarNoonLocal":"12:12","dayLengthHours":11.808543752613492,"dayLengthDisplay":"11 Hours 48 Mins 31 Secs","nightLengthDisplay":"12 Hours 11 Mins 29 Secs","moonriseLocal":"08:31","moonsetLocal":"21:41","rahuKala":{"name":"Rāhu Kāla","start":"13:40","end":"15:09","startHours":13.672803453578918,"endHours":15.148871422655606,"quality":"inauspicious"},"yamaganda":{"name":"Yamaganda","start":"06:18","end":"07:46","startHours":6.2924636081954874,"endHours":7.768531577272174,"quality":"inauspicious"},"gulika":{"name":"Gulika Kāla","start":"09:15","end":"10:43","startHours":9.24459954634886,"endHours":10.720667515425546,"quality":"inauspicious"},"durMuhurta":[{"name":"Dur Muhūrta","start":"09:03","end":"09:26","startHours":9.047790483805302,"endHours":9.441408608892418,"quality":"avoid"}],"varjyam":{"name":"Varjyam","start":"06:47","end":"07:06","startHours":6.784486264554383,"endHours":7.099380764624076,"quality":"avoid"},"abhijit":{"name":"Abhijit Muhūrta","start":"11:48","end":"12:35","startHours":11.803117359415117,"endHours":12.590353609589348,"quality":"auspicious"},"brahmaMuhurta":{"name":"Brahma Muhūrta","start":"04:43","end":"05:30","startHours":4.717991107847022,"endHours":5.505227358021255,"quality":"auspicious"},"pratahSandhya":{"name":"Prātaḥ Sandhyā","start":"05:19","end":"06:18","startHours":5.308418295477696,"endHours":6.2924636081954874,"quality":"auspicious"},"vijayaMuhurta":{"name":"Vijaya Muhūrta","start":"14:10","end":"14:57","startHours":14.164826109937817,"endHours":14.95206236011205,"quality":"auspicious"},"godhuliMuhurta":{"name":"Godhūli Muhūrta","start":"17:54","end":"18:18","startHours":17.90100736080898,"endHours":18.301007360808978,"quality":"auspicious"},"sayahnaSandhya":{"name":"Sāyāhna Sandhyā","start":"18:06","end":"18:36","startHours":18.10100736080898,"endHours":18.593030017167873,"quality":"auspicious"},"amritKala":{"name":"Amṛta Kāla","start":"17:51","end":"19:36","startHours":17.85100736080898,"endHours":19.60100736080898,"quality":"auspicious"},"nishitaMuhurta":{"name":"Niśīta Muhūrta","start":"23:48","end":"00:35","startHours":23.80311735941512,"endHours":24.59035360958935,"quality":"auspicious"},"dayChoghadiyas":[{"name":"Śubha","start":"06:18","end":"07:46","startHours":6.2924636081954874,"endHours":7.768531577272174,"quality":"auspicious"},{"name":"Roga","start":"07:46","end":"09:15","startHours":7.768531577272174,"endHours":9.24459954634886,"quality":"inauspicious"},{"name":"Udveg","start":"09:15","end":"10:43","startHours":9.24459954634886,"endHours":10.720667515425546,"quality":"inauspicious"},{"name":"Chala","start":"10:43","end":"12:12","startHours":10.720667515425546,"endHours":12.196735484502234,"quality":"neutral"},{"name":"Labha","start":"12:12","end":"13:40","startHours":12.196735484502234,"endHours":13.672803453578918,"quality":"auspicious"},{"name":"Amṛta","start":"13:40","end":"15:09","startHours":13.672803453578918,"endHours":15.148871422655606,"quality":"auspicious"},{"name":"Kāla","start":"15:09","end":"16:37","startHours":15.148871422655606,"endHours":16.624939391732294,"quality":"inauspicious"},{"name":"Śubha","start":"16:37","end":"18:06","startHours":16.624939391732294,"endHours":18.10100736080898,"quality":"auspicious"}],"nightChoghadiyas":[{"name":"Amṛta","start":"18:06","end":"19:37","startHours":18.10100736080898,"endHours":19.62493939173229,"quality":"auspicious"},{"name":"Kāla","start":"19:37","end":"21:09","startHours":19.62493939173229,"endHours":21.148871422655606,"quality":"inauspicious"},{"name":"Śubha","start":"21:09","end":"22:40","startHours":21.148871422655606,"endHours":22.67280345357892,"quality":"auspicious"},{"name":"Roga","start":"22:40","end":"00:12","startHours":22.67280345357892,"endHours":24.196735484502234,"quality":"inauspicious"},{"name":"Udveg","start":"00:12","end":"01:43","startHours":24.196735484502234,"endHours":25.720667515425546,"quality":"inauspicious"},{"name":"Chala","start":"01:43","end":"03:15","startHours":25.720667515425546,"endHours":27.24459954634886,"quality":"neutral"},{"name":"Labha","start":"03:15","end":"04:46","startHours":27.24459954634886,"endHours":28.76853157727217,"quality":"auspicious"},{"name":"Amṛta","start":"04:46","end":"06:18","startHours":28.76853157727217,"endHours":30.292463608195487,"quality":"auspicious"}],"horas":[{"name":"Hora 1","start":"06:18","end":"07:18","startHours":6.2924636081954874,"endHours":7.2924636081954874,"planetary_lord":"Jupiter"},{"name":"Hora 2","start":"07:18","end":"08:18","startHours":7.2924636081954874,"endHours":8.292463608195487,"planetary_lord":"Saturn"},{"name":"Hora 3","start":"08:18","end":"09:18","startHours":8.292463608195487,"endHours":9.292463608195487,"planetary_lord":"Moon"},{"name":"Hora 4","start":"09:18","end":"10:18","startHours":9.292463608195487,"endHours":10.292463608195487,"planetary_lord":"Mercury"},{"name":"Hora 5","start":"10:18","end":"11:18","startHours":10.292463608195487,"endHours":11.292463608195487,"planetary_lord":"Venus"},{"name":"Hora 6","start":"11:18","end":"12:18","startHours":11.292463608195487,"endHours":12.292463608195487,"planetary_lord":"Sun"},{"name":"Hora 7","start":"12:18","end":"13:18","startHours":12.292463608195487,"endHours":13.292463608195487,"planetary_lord":"Mars"},{"name":"Hora 8","start":"13:18","end":"14:18","startHours":13.292463608195487,"endHours":14.292463608195487,"planetary_lord":"Jupiter"},{"name":"Hora 9","start":"14:18","end":"15:18","startHours":14.292463608195487,"endHours":15.292463608195487,"planetary_lord":"Saturn"},{"name":"Hora 10","start":"15:18","end":"16:18","startHours":15.292463608195487,"endHours":16.292463608195487,"planetary_lord":"Moon"},{"name":"Hora 11","start":"16:18","end":"17:18","startHours":16.292463608195487,"endHours":17.292463608195487,"planetary_lord":"Mercury"},{"name":"Hora 12","start":"17:18","end":"18:18","startHours":17.292463608195487,"endHours":18.292463608195487,"planetary_lord":"Venus"},{"name":"Hora 13","start":"18:18","end":"19:18","startHours":18.292463608195487,"endHours":19.292463608195487,"planetary_lord":"Sun"},{"name":"Hora 14","start":"19:18","end":"20:18","startHours":19.292463608195487,"endHours":20.292463608195487,"planetary_lord":"Mars"},{"name":"Hora 15","start":"20:18","end":"21:18","startHours":20.292463608195487,"endHours":21.292463608195487,"planetary_lord":"Jupiter"},{"name":"Hora 16","start":"21:18","end":"22:18","startHours":21.292463608195487,"endHours":22.292463608195487,"planetary_lord":"Saturn"},{"name":"Hora 17","start":"22:18","end":"23:18","startHours":22.292463608195487,"endHours":23.292463608195487,"planetary_lord":"Moon"},{"name":"Hora 18","start":"23:18","end":"00:18","startHours":23.292463608195487,"endHours":24.292463608195487,"planetary_lord":"Mercury"},{"name":"Hora 19","start":"00:18","end":"01:18","startHours":24.292463608195487,"endHours":25.292463608195487,"planetary_lord":"Venus"},{"name":"Hora 20","start":"01:18","end":"02:18","startHours":25.292463608195487,"endHours":26.292463608195487,"planetary_lord":"Sun"},{"name":"Hora 21","start":"02:18","end":"03:18","startHours":26.292463608195487,"endHours":27.292463608195487,"planetary_lord":"Mars"},{"name":"Hora 22","start":"03:18","end":"04:18","startHours":27.292463608195487,"endHours":28.292463608195487,"planetary_lord":"Jupiter"},{"name":"Hora 23","start":"04:18","end":"05:18","startHours":28.292463608195487,"endHours":29.292463608195487,"planetary_lord":"Saturn"},{"name":"Hora 24","start":"05:18","end":"06:18","startHours":29.292463608195487,"endHours":30.292463608195487,"planetary_lord":"Moon"}],"taraBala":{"favorable_nakshatras":["Aśvinī","Bharaṇī","Punarvasu","Puṣya","Aśleṣā","Maghā","Pūrva Phalgunī","Viśākhā","Anurādhā","Jyeṣṭhā","Mūla","Pūrva Āṣāḍhā","Pūrva Bhādrapadā","Uttara Bhādrapadā","Revatī"],"unfavorable_nakshatras":["Kṛttikā","Rohiṇī","Mṛgaśirā","Ārdrā","Uttara Phalgunī","Hasta","Citrā","Svātī","Uttara Āṣāḍhā","Śravaṇa","Dhaniṣṭhā","Śatabhiṣaj"],"nature":"Janma-tara if same nakshatra; favorable for 15 nakshatras"},"chandraBala":{"favorable_rashis":["Meṣa","Karka","Siṃha","Tulā","Dhanu","Mīna"],"unfavorable_rashis":["Vṛṣabha","Mithuna","Kanyā","Vṛścika","Makara","Kumbha"]},"dishaShool":"South (Dakṣiṇa)","chandraVasa":"North","rahuVasa":"North-West","anandadiYoga":{"name":"Dhūmra","quality":"Inauspicious"},"drikRitu":"Varṣā (Monsoon) (Drik)","vedicRitu":"Varṣā (Monsoon)","drikAyana":"Dakṣiṇāyana","vedicAyana":"Dakṣiṇāyana","meta":{"method":"BOB-History Sūrya-Siddhānta + Vidhyamitra Tier-2 spherical localization (Drikpanchang-parity)","declination":3.8738880219676126,"eotMinutes":4.753870929866006,"ayanamsa":24.1142}},"calendars":{"vikram_samvat":2075,"vikram_samvatsara":"Virodhakṛt","saka_samvat":1940,"saka_samvatsara":"Vilambī","bengali_samvat":1425,"malayalam_era":1194,"nanakshahi_year":549,"lunar_month":"Bhādrapada","lunar_month_paksha_full":"Bhādrapada Śukla Pakṣa","solar_month":"Siṃha (Āvaṇi)","ritu":"Varṣā (Monsoon)","display_summary":"Bhādrapada Śukla Caturthī · Vikram 2075 Virodhakṛt · Śaka 1940 Vilambī"},"festivals":[{"id":"ganesha-chaturthi","name":"Gaṇeśa Caturthī","name_sanskrit":"गणेश चतुर्थी","tradition":"Pan-Hindu","associated_deity":"Gaṇeśa","significance":"Gaṇeśa's birth day; 11-day festival in Maharashtra.","vrata":false,"detection":{"tithi_number":4,"tithi_paksha":"Śukla","lunar_month":"Bhādrapada"},"precedence":1},{"id":"simha-sankranti","name":"Siṁha Saṅkrānti","name_sanskrit":"सिंह सङ्क्रान्ति","tradition":"Pan-Hindu","significance":"Sun enters Leo.","vrata":false,"detection":{"sun_rashi":"Siṃha"},"precedence":5},{"id":"vinayaka-chaturthi","name":"Vināyaka Caturthī (monthly)","name_sanskrit":"विनायक चतुर्थी","tradition":"Pan-Hindu","associated_deity":"Gaṇeśa","significance":"Monthly Śukla-pakṣa Caturthī; auspicious for new ventures.","vrata":true,"detection":{"tithi_number":4,"tithi_paksha":"Śukla"},"precedence":6}],"todays_walk":{"walk":{"id":"guru-walk","name":"Bṛhaspati Walk","name_sanskrit":"गुरु यात्रा","type":"graha","description":"Wisdom transmission + BG 4.34.","step_count":8,"url":"/walk/guru-walk"},"reason":"Guruvāra (Thursday) — 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 13, 2018 CE · Perth, Australia · Vidhyamitra","description":"September 13, 2018 CE for Perth, Australia: Śukla Caturthī, sūryodaya 06:18, sūryāsta 18:06.","schema_org_type":"Article","canonical":"https://vidhyamitra.com/city/perth/2018-09-13","hreflang_alternates":{"en":"https://vidhyamitra.com/city/perth/2018-09-13","sa":"https://sa.vidhyamitra.com/city/perth/2018-09-13","hi":"https://hi.vidhyamitra.com/city/perth/2018-09-13","x-default":"https://vidhyamitra.com/city/perth/2018-09-13"}},"provenance":[{"pillar":"BOB-History","pillar_version":"2.12.0","method":"Sūrya-Siddhānta first-principles + Bhāskara II + Kerala-school (Mādhava-Nīlakaṇṭha) corrections","retrieved_at":"2026-05-15T08:48:06.551Z","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":"2026-05-15T08:48:06.551Z","verification":{"type":"community-validated","markers":["matches Drikpanchang ±1 minute on Narasiṁha Jayantī 2026"],"confidence":"verified"}}],"meta":{"generated_at":"2026-05-15T08:48:06.551Z","pillar_versions":{"Sūrya-Siddhānta":"Pūrṇa","Vidhyamitra-Tier2":"Pūrṇa"}}}