We say in Kiddush Levanah,
יהי רצון מלפניך...למלאת פגימת הלבנה ולא יהיה בה שום מיעוט
May it be Your will...to fill the reduction of the moon, and that there should be no diminishment in it.
Since the waxing and waning of the moon is a result of its orbiting the Earth, does this mean that it will remain on the opposite side of the Earth from the Sun in the future?