29 1/2 days, or a month.
The penumbral phase of a lunar eclipse can last for four hours or so, but the total phase never lasts more than about 80 minutes.
The lunar cycle of phases is about 29.5 days. As the moon rotates and revolves around the earth, and the earth rotates and revolves around the sun, the shadows cast by the shifting positions of the moon and earth cause the moon to wane, wax, and "disappear". This is known as the lunar cycle.
There is no "last" in repeating cycles. Whatever phase you are thinking of, the next one restarts the series.
Any specific lunar phase can be observed only at the time when that lunar phase occurs, and not again for 29.53 days thereafter.
They last forever.
No.
The 'waxing gibbous' phase does.
Full.
Easily. The lunar eclipse of December 21, 2010 will last (lasted) about 5-1/2 hours, with the 'total' phase lasting 73 minutes.
We do . . . Full.
full moon phase
Full Moon.