The Islamic Calendar is a lunar calendar that is tied to the Moon’s phase cycle. Each month spans for a full moon, which is the period between one New Moon to another. This Moon phase covers all the stages of the Moon during a month. Therefore, the Islamic lunar Calendar was devised so that each month is able to be determined in relation to this cycle and thus is known as the Islamic lunar Calendar. The Gregorian calendar on the other hand, remains fixed and follows a cycle that doesn’t run on a lunar cycle.
As we all know, the Moon is a planet and it is not fixed by any celestial body. It rotates twenty-four hours every day and it moves around the earth at a very slow speed. In fact, it takes about half a year to move one degree on the Astronomical map. Hence, the Islamic lunar calendar is divided into four seasons or months, with each of them having about ten days in a year.
The Gregorian calendar on the other hand is a lot more complicated. It has forty-eight days in a year and each day is placed at a different place on the map. It also has eleven months and these are divided into four quarters, namely, the summer, the winter, the autumn and the spring. And the calendar uses the date as its base and hence, each quarter corresponds to a month.
The United States has its own set of laws pertaining to its calendar. Although the Gregorian calendar is widely used all over the country, there are some minor differences as far as how each state has been reckoned. For instance, in the state of Massachusetts, the location for the first day of the New Year is not observed, but the second and third days of September, Thanksgiving, Christmas and New Year’s are all included. Whereas, the September in the state of Massachusetts is not included and neither is the function which occurs on the first day of February, the latter two September dates are observed. However, the state of Rhode Island has made some amendments so that it can now be observed, as every other state.
Now we come to our Gregorian calendar. The first thing that will strike you about this calendar is that it is divided into four seasons. The spring, summer, Autumn and Winter, which are the only major parts of the year are reckoned in leap years. This is because the Julian calendar, which is used in the Gregorian calendar, has only twelve months and the Gregorian calendar is based on the lunar cycles that repeat itself every year.
The Indian calendar or the Indian traditional calendar also has forty-eight divisions. These divisions of days are also based on the lunar cycles and hence it follows a cycle of twenty-eight days. The Indian traditional calendar also has seventy weeks which are known as the Baisakhi months. This Indian calendar was earlier called the western calendar and is in fact, almost a replica of the Gregorian calendar. This calendar was however replaced by the new Indian calendar, which is used for both countries.
There is another Indian calendar known as theatha calendar, which is also in two sections. The first section covers the period between the first and the thirteenth day of the Hindu month Shravan. This is followed by the second section, which relates to the period between the completion of Magadh and the arrival of Ramayana at Bhaisasthan. This calendar has been in existence for about 400 years and it was the Gregorian calendar which made the anlas of the anlas.
The Golkula system is another interesting example of a lunar calendar which helps to keep track of time. The system was devised by Sarpagandha Sharananda who is believed to have lived in the Chalahada dynasty of southern India. The system divides the year into four seasons of spring, summer, late autumn and winter. This is followed by a transition period of a small number of days into the next season, which is autumn. For the four seasons there is an alignment of the celestial bodies with the Sun.