Yes, but this set in the Forgotten Realms. A feat from Lost Empires of Faerun grants a +2 spell caster level when casting under the light of the moon called Cormanthyran Moon Magic. If the 9th level cleric with Cormantyran Moon Magic and Craft Wondrous Item decided to enchant a Phylactery at nigh under moon light, their caster level is 9 + 2 = 11.
Remember that the moon stays in the sky roughly as long as the Sun does each day, just at different times.
