A solar calendar 날짜계산기 is a time system that marks seasons according to the apparent position of the Sun relative to the stars. This system is similar to the Gregorian calendar, which is used in many cultures today. But there are some differences between the Gregorian and solar calendars. Let’s take a look at some of them.
Sidereal solar calendar
The Sidereal solar calendar is a calendar that follows the movements of the sun and the moon in relation to one another. It is not based on the tropical movement of the Earth but on the apparent motion of the sun through the zodiac signs. Its most prominent example is the Hindu Calendar. This calendar has twelve solar months and two lunar months, while the Gregorian Calendar has 365 days and four seasons.
The Sidereal solar calendar follows the annual motion of the sun relative to the stellar zodiac. The year starts from the point when the sun passes the ecliptic longitude of Sagittarius A*, a radio source at the heart of the galaxy. In the year 2000 AD/CE, the equatorial coordinates of Sagittarius A* were 17h 45m, Dec -29d 0 m. This position is known as the solar New Year.
The sidereal solar calendar differs from the tropical calendar due to the precession of the equinoxes. As the Earth revolves around the sun, the vernal equinox moves closer to the Sun. The equinox returns to its position slightly before the following year. This effect is very small and very slow, though. The tropical calendar is about 20 minutes shorter than the sidereal solar calendar.
Lunisolar calendar
The lunisolar calendar is a type of calendar that many cultures use. It combines solar and lunar calendars to keep track of dates. These dates are based on the Moon’s phase at the time and the Sun’s position in Earth’s sky. For example, if you want to know the date of a lunar eclipse, you should use a lunisolar calendar.
Lunisolar calendars were first used by the Babylonians in 2000 B.C. They added a leap month to the lunar year and adjusted for climatic changes in the 365-day calendar. By the time of the Neo-Babylonian Empire, the lunisolar calendar had spread throughout the Eurasian continent except Egypt. The calendar was eventually passed to a Jew who was imprisoned by the Babylonians and is the basis of the Jewish calendar.
A lunisolar calendar is composed of two main parts: the solar year and the lunation. The solar year is the long-term time period in which the earth rotates around the sun. The month in the lunisolar calendar is named after the asterism that corresponds to the next full moon, which depends on the sun’s position in the sky. The lunar month is a full moon calendar month, and the full moon calendar month starts a fortnight before the amaant month.
Gregorian calendar
Pope Gregory instituted the Gregorian calendar in 1582, and it was soon adopted throughout the Catholic world. In October of 1582, Spain, Portugal, Austria, and Bohemia and Moravia all made the transition. Hungary and Prussia adopted the new calendar in 1610. Protestant countries did not adopt the Gregorian calendar right away. However, John Dee, an astronomer, devised a more precise calendar than Gregory’s, which was published in 1610.
Until 1752, the British Empire still used the Julian Calendar. As a result, dates in those years are often uncertain. Because of this, it is a good idea to write dates in both systems, such as “14 February 1699/1700”. This will ensure that the same event is recorded under both calendars.
Several other countries subsequently made the transition to the Gregorian calendar. Most did so by 1929, with China being the exception. Until that time, civil unrest had left the question of which calendar to use unresolved. Japan, however, accepted the Gregorian calendar for international trade with the west, despite using a local calendar for centuries.
Islamic calendar
Many Muslims use the Islamic calendar to keep track of religious events. Also called the lunar calendar or Hijri calendar, it has 365 days. It is used to determine the dates of festivals and other religious observances. Although the Islamic calendar is different from the Gregorian calendar, they share some common characteristics.
The Islamic calendar is based on the lunar cycle, which is 29-30 days long. The dates are based on the new crescent moon, which is visible on the 29th day of the previous month. It differs from the solar calendar in that odd-numbered months are 30 days long, while even-numbered months have 29 days.
The Islamic calendar is somewhat variable. Some Islamic holidays are moved up by 10-12 days every year in comparison to the Gregorian calendar. The Islamic calendar is used for religious purposes in most Muslim countries. However, most of these countries also follow the Gregorian calendar for agriculture and commerce.