The lunar calendar is a calendar that is based on the Moon’s cycle or phases. This is in contrast to the solar calendar which is based only on the solar year. The Gregorian calendar as we all know is the most common calendar is based on the solar calendar but was invented originally based on lunar calendar. There is a process called intercalation which states that a purely lunar calendar can be differentiated from lunisolar calendars in such a way that the lunar months need to be aligned like that in solar calendar 2018. When the months begin depends on the various forms of the moon like the full moon, crescent moon, half moon, and some of them are based on calculations. All phases of the moon have been given on it.
Lunar Calendar 2018
The length of each lunation is approximately 29.5 days that is 29 days , 12 hours , 44 minutes , and 3 seconds. The months in the lunar calendar varies between 29 and 30 days and is a common phenomenon. During a lunar year there are twelve lunation’s and hence the year is approximately 354 days or 354 days , 8 hours , 48 minutes , and 34 seconds. It is a common phenomenon to loose eleven days a year in comparison to Gregorian calendar. There are some pure lunar calendars like the Islamic calendar which has to repeat the cycle of Gregorian calendar after a gap of every 33 years.
The Gregorian calendar is the most common calendar that is used in almost every countries hut in order to find the national holidays and regional holidays , the lunar and lunisolar calendars are used in the old world till now. Some of the holidays are : –
3. New year
5. Chinese new year
6. Nepali new year
The warren field in Scotland is the first place where the lunar calendar was found and this dates back to 8000 BC. This was during the Mesolithic period. There are some scholars who argued that the moon calendar 2018 existed even before this time.
Moon Phase Calendar 2018
One important thing to note is that the calendars referred to as lunar calendars are basically the lunisolar calendars only. The process of intercalation is used to match the months according to the solar calendar. In ancient Egypt there were traces of solar civic calendar were found that were in accordance with the lunar calendar. The Chinese, Hindu, and the Thai calendars are present day lunisolar calendar and they often search what is a new moon and is the moon phase today?
New Moon Calendar 2018
Since the months are 29 or 30 days in length hence they are called synodic months and hence it leads to the lunar year being 11 days short of solar year. There are some lunar calendars that don’t use the intercalation like the Islamic calendar. But there are some that do calculations and add an extra month after every two to three years so that they are at match. The example of these calendars is Hebrew Calendar. In some lunisolar calendars some natural events occurring take a part to make some changes that are at par with the lunar cycle as well as solar cycle. An example of this kind of calendars is Banks Islands which always uses the mass of palolo worm to include three months additional in the calendar.
At what time the day will start differs in both the lunar calendar as well as the lunisolar calendar. Also there is a difference that on which day a month will start. For example :- in the Chinese calendar a new day of the month is started when there is a new moon at some particular time zone. There are calendars in which the new day of every month begins after full moon or new moon. The example of this type of calendar is Hindu calendar. Some calendar find the day of month by seeing the first sighting of the lunar crescent and the calendar using this concept is Hebrew calendar.
Moon Phase Calendar 2018
There is an average value for the length of every lunar cycle which varies accordingly. These depend on the observations on the weather conditions and subject of uncertainty. In order to fix the above uncertainties there have been several arithmetic rules that have been discovered and made to overcome it and approximately give the date of the new month and the particular day.
The value of 29.530589 days or 29 days , 12 hours , 44 minutes , and 3 seconds , is the average value of the synodic month. It is in consideration with the fact that the days of the months are either twenty nine days or thirty days. These days are called as hollow or full. There is a term in mathematics called as the continuous fraction which helps in determining the distribution of hollow and full months. These functions are also used in examining approximation of successive lengths of months as a fraction of a day. There is a list below showing the number of days in the numerator and the months after that in the denominator : –
1. 29 / 1 ( After 2 months add 1 day )
2. 30 / 1 ( After 2 months add 1 day )
3. 59 / 2 ( After 2.6 years add 1 day )
4. 443 / 15 ( After 30 years add 1 day )
5. 502 / 17 (After 70 years add 1 day )
6. 945 / 32 (After 222 years add 1 day , can be expressed in binary exactly : 11101.10001₂ )
7. 1447 / 49 (After 3 millennia add 1 day )
8. 25101 / 850 ( if there is change in synodic month value)
2018 Lunar Calendar
The fractions shown above are used to make a lunar calendar and also can be used to make a lunisolar calendar by doing a combination with a solar calendar to make it. In the above list, in the 7th point we can see that there is a 49 month calendar which was proposed as an alternative by Issac Newton for the Easter Computation in the year 1700 around.