Differnce between synodic, sideral, nodical, and anomalistic months in general.?

Answer 1

http://en.wikipedia.org/wiki/Orbital_period
good starting point

* The sidereal period is the time that it takes the object to make one full orbit around the Sun, relative to the stars. This is considered to be an object's true orbital period.
* The synodic period is the time that it takes for the object to reappear at the same point in the sky, relative to the Sun, as observed from Earth; i.e. returns to the same elongation. This is the time that elapses between two successive conjunctions with the Sun and is the object's Earth-apparent orbital period. The synodic period differs from the sidereal period since Earth itself revolves around the Sun.
* The draconitic period is the time that elapses between two passages of the object at its ascending node, the point of its orbit where it crosses the ecliptic from the southern to the northern hemisphere. It differs from the sidereal period because the object's line of nodes typically precesses or recesses slowly.
* The anomalistic period is the time that elapses between two passages of the object at its perihelion, the point of its closest approach to the Sun. It differs from the sidereal period because the object's semimajor axis typically precesses or recesses slowly.
* The tropical period, finally, is the time that elapses between two passages of the object at right ascension zero. It is slightly shorter than the sidereal period because the vernal point precesses.

Answer 2

The sidereal month is the time it takes the moon to make one complete orbit around the Earth and it is about 27.3 days.

The synodic month is the amount of time between solar conjunctions of the moon. It is the month on which the lunar phases repeat in a cycle and is often called a lunation, and is what the month was originally based on. It is about 29.5 days on average. The total length varies over the course of the year.

The draconic month (what you call the nodical month) is the time it takes for the moon to return to the same node of it's orbit. Because the nodes precess (or move backward) along the orbit slowly, this period is slightly shorter than the sidereal period, about 27.2 days.

The anomalistic month is the amount of time it takes the moon to return to the same apside (perigee or apogee). The apsides recess (move forward) along the orbit slowly so this period is slightly longer than the sidereal period, about 27.5 days.

I hope that helps.

Answer 3

Wikipedia has a lot of info