synodic month
Quick Summary
The synodic month is a unit of time used in astronomy, specifically referring to the period of the Moon's phases as seen from Earth. This cycle averages 29.530588 mean solar days, which is approximately 29 days, 12 hours, and 44 minutes. This is the time it takes for the Moon to complete a cycle of phases, such as from one new moon to the next.12
The synodic month is crucial for many calendars, particularly lunisolar ones, where months are based on the Moon's phases. For example, the Islamic calendar begins each month with the new moon. While the synodic month is the basis for calendar months, its length is not perfectly aligned with the solar year, leading to the need for intercalations (adding days) in some calendar systems.32
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- lunar calendar
…on a year consisting of synodic months—i.e., complete cycles of phases of the Moon. In every solar year (or year of the seasons) there are about 12.37 synodic months. Therefore, if a lunar-year calendar is to be kept in step with the seasonal year, a periodic intercalation (addition) of days…
Read More…on a year consisting of synodic months—i.e., complete cycles of phases of the Moon. In every solar year (or year of the seasons) there are about 12.37 synodic months. Therefore, if a lunar-year calendar is to be kept in step with the seasonal year, a periodic intercalation (addition) of days…
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calendarTime determination by stars, Sun, and Moon…the phases; this interval, the synodic month, is now known to be 29.53059 days. The synodic month grew to be the basis of the calendar month.
Read More…the phases; this interval, the synodic month, is now known to be 29.53059 days. The synodic month grew to be the basis of the calendar month.
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MoonPrincipal characteristics of the Earth-Moon system531 days, the synodic month, or synodic revolution period of the Moon. As a result, the Moon’s terminator—the dividing line between dayside and nightside—moves once around the Moon in this synodic period, exposing most locations to alternating periods of sunlight and darkness each nearly 15 Earth days long.…
Read More531 days, the synodic month, or synodic revolution period of the Moon. As a result, the Moon’s terminator—the dividing line between dayside and nightside—moves once around the Moon in this synodic period, exposing most locations to alternating periods of sunlight and darkness each nearly 15 Earth days long.…
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eclipseCycles of eclipses…occurrence of eclipses is the synodic month—i.e., the interval between successive new moons, as seen from Earth.
Read More…occurrence of eclipses is the synodic month—i.e., the interval between successive new moons, as seen from Earth.
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