Lunar month

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Lunar month

In lunar calendar

Lunar calendar

A lunar calendar is a calendar that is based on cycles of the moon phase. The only widely used purely lunar calendar is the Islamic calendar or Hijri calendar, whose year always consists of 12 lunar months....
s, a lunar month is the time between two identical syzygies

Syzygy

In broadest terms, Syzygy is a kind of unity, especially through coordination or alignment, most commonly used in the astronomical and/or astrological sense....
(new moon

New moon

Full moon

Full moon is a lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. More precisely, a full moon occurs when the geocentric apparent longitudes of the Sun and Moon differ by 180 degrees; the Moon is then in opposition with the Sun....
s). There are many variations. In Middle-Eastern and European traditions, the month starts when the young crescent moon

New moon

In astronomical terminology, the new moon is the lunar phase that occurs when the Moon, in its monthly orbital motion around Earth, lies between Earth and the Sun, and is therefore in Conjunction with the Sun as seen from Earth....
becomes first visible at evening after conjunction with the Sun 1 or 2 days before that evening (e.g. in the Islamic calendar

Islamic calendar

The Islamic calendar or Muslim calendar or Hijri calendar is a lunar calendar used to date events in many predominantly Muslim countries, and used by Muslims everywhere to determine the proper day on which to celebrate Islamic holy days and festivals....
). In ancient Egypt the lunar month began on the day when the moon could no longer be seen just before sunrise.

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Where can I find an internet calendar of the times/dates of north and south declinations of the moon...

Encyclopedia

In lunar calendar

Lunar calendar

Syzygy

In broadest terms, Syzygy is a kind of unity, especially through coordination or alignment, most commonly used in the astronomical and/or astrological sense....
(new moon

New moon

Full moon

New moon

Islamic calendar

Hebrew calendar

The Hebrew calendar or Jewish calendar is a lunisolar calendar used by Jews, now predominantly for religious purposes. It is used to reckon the Jewish New Year and dates for Jewish holidays, and also to determine appropriate Torah reading of Torah portions, Yahrzeits , and daily Psalm reading, among many ceremonial uses....
), or use a tabular scheme (Ecclesiastical lunar calendar

Computus

Computus is the calculation of the date of Easter in the Christian calendar. The name has been used for this procedure since the early Middle Ages, as it was one of the most important computations of the age....
). Yet others run from full moon

Full moon

Full moon is a lunar phase that occurs when the Moon is on the opposite side of the Earth from the Sun. More precisely, a full moon occurs when the geocentric apparent longitudes of the Sun and Moon differ by 180 degrees; the Moon is then in opposition with the Sun....
to full moon. Calendars count integer days, so months may be 29 or 30 days in length, in some regular or irregular sequence. But all lunar months approximate the mean length of the synodic month

Month

The month is a unit of time, used with calendars, which is approximately as long as some natural Orbital period related to the motion of the Moon; month and Moon are cognates....
of approximately 29.53059 day

Day

A day is a units of measurement of time equivalent to approximately 24 hours. It is not an International System of Units unit but it is accepted for use with SI....
s (29 days, 12 hour

Hour

The hour is a unit of time. It is not an SI unit but is Non-SI units accepted for use with SI....
s, 44 minute

Minute

A minute is a unit of measurement of time or of angle.The minute is a Unit of measurement of time equal to 1/60th of an hour or 60 seconds. In the Coordinated Universal Time time scale, a minute occasionally has 59 or 61 seconds; see leap second....
s and 3 second

Second

The second , sometimes abbreviated sec., is the name of a units of measurement of time, and is the International System of Units SI base unit of time....
s).

There are several different ways of expressing the lunar month.

The Moon's orbital period
Orbital period

The orbital Periodicity is the time taken for a given object to make one complete orbit about another object.When mentioned without further qualification in astronomy this refers to the sidereal period of an astronomical object, which is calculated with respect to the stars....
in a non-rotating frame of reference (which on average is equal to its rotation period
Rotation period

The rotation period of an astronomy astronomical object is the time it takes to complete one revolution around its axis of rotation relative to the background stars....
) is about 27.32 days (27 days, 7 hours, 43 minutes, 11.6 seconds). This is known as a sidereal month and is measured by observing how long it takes the Moon to pass a fixed star
Star

A star is a massive, luminous ball of Plasma that is held together by its own gravity. The nearest star to Earth is the Sun, which is the source of most of the energy on Earth....
on the celestial sphere
Celestial sphere

In astronomy and navigation, the celestial sphere is an imagination rotation sphere of "gigantic radius", concentric spheres and coaxial with the Earth....
.
A synodic month is 29.53 days (29 days, 12 hours, 44 minutes, 2.8 seconds) and is measured from New Moon to New Moon. A New Moon is defined to occur when the Moon has the same ecliptic longitude
Ecliptic longitude

Ecliptic longitude is one of the co-ordinates which can be used to define the location of an astronomical object on the celestial sphere in the ecliptic coordinate system....
as the Sun, as seen from the center of the Earth: i.e. when the Sun, Moon and Earth are almost on one line. A synodic month is longer than a sidereal month because the Earth-Moon system is orbiting the Sun in the same direction as the Moon is orbiting the Earth. Therefore, the Sun appears to move with respect to the stars, and it takes about 2.2 days longer for the Moon to return to the apparent position of the Sun. The synodic month is the most common way of expressing the lunar cycle.
An anomalistic month is the Moon's orbital period
Orbital period

The orbital Periodicity is the time taken for a given object to make one complete orbit about another object.When mentioned without further qualification in astronomy this refers to the sidereal period of an astronomical object, which is calculated with respect to the stars....
measured from perigee to perigee - the point in the Moon's orbit when it is closest to Earth. An anomalistic month is about 27.55 days on average.
The tropical month is the time for the Moon to return to the same ecliptic longitude
Ecliptic longitude

Ecliptic longitude is one of the co-ordinates which can be used to define the location of an astronomical object on the celestial sphere in the ecliptic coordinate system....
, i.e. measured from the equinox
Equinox

Equinoxes occur twice a year, when the tilt of the Earth's axis is inclined neither away from nor toward the Sun, causing the Sun to be located vertically above a point on the equator....
; it is slightly shorter than the sidereal month because of precession of the equinoxes
Precession of the equinoxes

In astronomy, precession refers to a gravitationally-induced slow but continuous change in an astronomical body's rotational axis or orbital path....
.
The draconic month or nodal month is the period in which the Moon returns to the same node
Lunar node

The lunar nodes are the orbital nodes of the Moon, that is, the points where the Planetary orbit of the Moon crosses the ecliptic . The ascending node is where the moon crosses to the north of the ecliptic....
of its orbit; the nodes are the two points where the Moon's orbit crosses the plane of the Earth's orbit. Its duration is about 27.21 days on average.