During a night instructional flight, the flight instructor simulated an engine failure while on the downwind leg of the traffic pattern. As the airplane approached the runway with the landing light off, the flight instructor noticed that they were low on the approach. When the instructor asked the student if the landing light was on, the student pilot promptly answered “no” and turned it on. The airplane struck trees at the same moment, which resulted in substantial damage to the wings and tail. A review of meteorological and astronomical data revealed there was a broken cloud layer at 6,000 feet above ground level and the phase of the moon was a waning crescent with 1% of the Moon’s visible disk illuminated. Further review indicated that the Moon had set about 1 hour and 43 minutes prior to the accident. The pilot reported no mechanical malfunctions or anomalies that would have precluded normal operation.