A naked-eye observer who tracks the rise and set position of the moon on the horizon will see that for half a "month" the position moves farther south each day and then for another half "month" moves farther north each day. How long is this "month"?

This seems copy/pasted. Please forgive me if it's not, but is this a homework question you joined to ask?

 

It's OK if it is, but it's important for us to know.

If you had gone to Wikipedia.org and typed "lunar month" you would have gotten your answer. Amazing how much Wiki knows.

 

Wiki says a lunar month is approx. 29.53 days.

 

Try Wiki first. If that doesn't work, ask here.

 

http://en.wikipedia.org/wiki/Lunar_month

This seems copy/pasted. Please forgive me if it's not, but is this a homework question you joined to ask?

 

It's OK if it is, but it's important for us to know.

 

It is not a homework question. I am constructing a Ppt on archeoastronomy and I am trying to find the number of days for the moon to go from its most northerly rising or setting point on the horizon to its most southern point, and back again. I am aware of the longer 18.6 year cycle but I have not able to find the length of this shorter cycle. There are several versions of a lunar "month" and I am not sure what this one is.

 

It is not a homework question. I am constructing a Ppt on archeoastronomy and I am trying to find the number of days for the moon to go from its most northerly rising or setting point on the horizon to its most southern point, and back again. I am aware of the longer 18.6 year cycle but I have not able to find the length of this shorter cycle. There are several versions of a lunar "month" and I am not sure what this one is.