Navami and the Goddess

Navami is the ninth tithi of the bright fortnight, a Rikta tithi in the fivefold grouping and so generally reckoned unfavourable for new ventures, again with its festivals excepted. Its presiding deity is Durga, and the ninth tithi is central to the Goddess festivals: Maha Navami closes the main days of Navaratri, and Rama Navami, in the bright fortnight of Chaitra, celebrates the birth of Rama on this tithi. The waxing Moon is now well past its first quarter and growing toward gibbous. The panchanga marks the day with the Rikta caution for routine matters while treating its devotional observances as among the most sacred of the year. These attributions belong to the festival and calendar tradition rather than to astronomy.

Rama Navami's date, the ninth tithi of the bright fortnight of Chaitra, places it near the spring equinox in the solar year and at the very start of the traditional Hindu new year cycle in several regional calendars, which some commentators read as fitting for a festival celebrating a divine birth and a fresh beginning. The Goddess festivals of Navami are calculated according to which tithi is current at a specified time of day, commonly midday or madhyahna, rather than simply at sunrise, a distinction the panchanga applies to several major festival tithis precisely because a tithi that changes partway through daylight hours would otherwise leave the correct date for the observance ambiguous.