In Vedic timekeeping, a tithi is a "duration of two faces of moon that is observed from earth", known as milа̄lyа̄ (Newar: 𑐩𑐶𑐮𑐵𑐮𑑂𑐫𑐵𑑅, मिलाल्याः) in Nepal Bhasa, or the time it takes for the longitudinal angle between the Moon and the Sun to increase by 12°. In other words, a tithi is a time duration between the consecutive epochs that correspond to when the longitudinal angle between the Sun and the Moon is an integer multiple of 12°. Tithis begin at varying times of day and vary in duration approximately from 19 to 26 hours. Every day of a lunar month is called tithi.
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👉 Tithi in the context of Ashtami
Ashtami (अष्टमी aṣṭamī) is the eighth day (Tithi) of Hindu lunar calendar.
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Tithi in the context of Paksha
Paksha (Sanskrit: पक्ष, romanized: pakṣa) refers to a fortnight period consisting of various lunar phases in a month of the Hindu lunar calendar. Literally meaning "side" in Sanskrit, it refers to the periods between amavasya (new moon) and purnima (full moon), and vice versa.
A lunar month in the Hindu calendar has two fortnights, with each fortnight subdivided into lunar days called tithis. A paksha consists of 15 such tithis, each of which correspond to a 12-degree angular motion of the Moon. The fortnight between amavasya and purnima is called as Shukla Paksha (bright side) or Gaura Paksha, which corresponds to the period of the waxing moon. The second fortnight is called Krishna Paksha (dark side) or Vadhya Paksha' and corresponds to the period of the waning moon. Amavasya corresponds to the period when the Moon is within 12 degrees of angular distance from the Sun before their conjunction.
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