Hindu festivals are defined by a lunar calendar, which divides the year into twelve lunar months.
The lunar month is split into two half with fifteen days
each.
The lunar month in northern India starts with the dark
(krishna) half of the moon, when it is declining.
The new moon marks the conclusion of this phase, which lasts
fifteen days.
The bright (shukla) part of the month, while the moon is
waxing, follows.
The full moon marks the conclusion of this phase, which
lasts fifteen days.
The first day of the following lunar month is the day after
the full moon, and so on.
The name of the month, the half (light or dark), and the
lunar day are all used to identify any specific lunar day (1 to 15).
The sequence is inverted in southern India, with the lunar
month beginning with the light half and ending with the new moon.
The lunar month, like many Hindu concepts of time, depicts
changing moments of auspiciousness and inauspiciousness, with peaks and valleys
denoting more or less auspicious times.
With its symbolism of fullness, richness, and light, the
full moon is usually fortunate.
It is said that religious ceremonies conducted on this day
have the same amount of virtue as those performed over the course of a month.
The new moon is a more confusing moment, with its
connotations of darkness and nothingness.
The new moon may be very fortunate at times, such as on the
occasion of a Somavati Amavasya (new moon falling on Monday).
The new moon coincides with many significant holidays (such
as Diwali).
Regardless, the new moon is less fortunate than the full
moon.
Various days are identified with distinct deities within
each fort night, and their devotees (bhakta) frequently perform specific
ceremonies on those days: The deity Vishnu is honored on the eleventh day
(ekadashi), the Goddess on the eighth day (ashtami), the god Shiva on the
thirteenth and fourteenth days (trayo dashi) and the god Ganesh on the fourth
day (chaturthi).
As previously stated, practically all Hindu celebrations are
based on the lunar calendar.
An intercalary month is introduced every 212 years to
rectify the disparity between the lunar and solar years (approximately eleven
days), and so retain these festivals at around the same time every year.
Although the additional month preserves the calendar in
balance, it is thought to be exceedingly inauspicious, maybe due to its rarity.
People take usual measures to protect themselves during unfavorable periods throughout this month, such as deferring new activities
until the end of the month and praying to protective deities until the end of
the month.
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