Earliest time for kiddush levanah

Hi,

Kiddush Levanah is meant to be recited at the point in the month when the moon's growth is clear.

There is some debate as to how long one must wait before this point is reached, but the consensus is that one may recite Kiddush Levanah after 72 hours from the time of the molad (the ceremonial point at which we consider the moon to have begun its new cycle).

(Mishneh Berurah 426:20)

Have a great day,
Mordechai