johannes kepler invented the calendar system we use today.
johannes kepler invented the calendar system we use today.
who invented the calendar system we use today?
johannes kepler
a lunar calendar is a calendar based upon the monthly cycles of the moon's phases (synodic months), in contrast to solar calendars, whose annual cycles are based only directly upon the solar year. the most commonly used calendar, the gregorian calendar, is a solar calendar system that originally evolved out of a lunar calendar system. a purely lunar calendar is also distinguished from a lunisolar calendar, whose lunar months are brought into alignment with the solar year through some process of intercalation. the details of when months begin varies from calendar to calendar, with some using new, full, or crescent moons and others employing detailed calculations.
lunar calendar
there have been a number of modern proposals for reform of the calendar, such as the world calendar, international fixed calendar, holocene calendar, and, recently, the hanke-henry permanent calendar. such ideas are mooted from time to time but have failed to gain traction because of the loss of continuity, massive upheaval in implementation, and religious objections.









































section::::calendar systems.









































a full calendar system has a different calendar date for every day. thus the week cycle is by itself not a full calendar system; neither is a system to name the days within a year without a system for identifying the years.
calendar