This calendar has Indian holiday indication with phases of the moon.
There are many variations of Hindu calendars (also called Indian calendars). Some regions use a solar calendar based on what are the signs of the Zodiac in English. Other regions use a luni-solar calendar with months based on the lunar cycle and years of either 12 or 13 months. The Gregorian calendar is also widely used in India for civil purposes.
Many Hindus use both a lunar and a solar calendar simultaneously, as part of a panchangam. The word means "five limbs." The five parts of a panchangam depend on: 1. the lunar day, 2. the lunar month, 3. the half-day, 4. the angle of the sun and moon, and 5. the solar day.
Some lunar calendars start each month with a new moon, while others start each month with a full moon, and Hindu calendars don't all agree on when a year starts, either.
In an attempt to get everyone in India to use the same calendar, the government introduced an Indian National calendar in 1957. It is a solar calendar with either 365 or 366 days in a year, leap year rules identical to those in the Gregorian calendar, but with years starting near the vernal equinox (March 22 in regular years, March 21 in leap years) and traditional Indian names for the months. Years are counted from the first year of the Saka era, (AD 78) The year is also divided into 6 seasons of two months each.
The ecliptic, the apparent path of the sun through the sky, is dividied into 12 rashi, which are the same as the signs of the zodiac in English. The solar months are based on the rashi.
The ecliptic is also divided into 27 lunar mansions, the nakshatra, which means stars in English. However, paradoxically, the nakshatras sometimes also refer to zodical. There are approximately 3 nakshatras in each rashi. Each nakshatra has four divisions knowns as paadams. Some nakshatras spill over two rashis based on which paadam they come under.
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