What is the moon phase if it reaches its highest point at 900pm?

If the moon reaches its highest point in the sky at 9:00 PM, it is likely in the waxing gibbous or full moon phase. A waxing gibbous moon rises in the afternoon and sets after midnight, while a full moon rises around sunset and sets at sunrise. Therefore, the specific phase depends on the exact date, but it is generally indicative of a later phase in the lunar cycle.