US NAVAL OBS.
Calvin Keys, 3/12/01
In summary, the moon was full on August 14, 1780, at 9:48 PM. It was waning at 99% full and 100% illuminated as the armies left their camps at 10:00 PM on August 15th, 1780. Moonrise on the 15th was at 7:53 PM in the East at 107.4 degrees. At 10:00 PM the moon was at 127.6 degrees southeast and 22.1 degrees above the horizon. By 1:25 AM on August 16th, 1780 the moon was at its highest point in the sky of the evening, at 41.5 degrees above the horizon and south at 180 degrees. When the armies met at 2:30am on August 16th, the moon was 39.2 degrees above the horizon and southwest at 201.3 degrees. This places the moon behind the British Army that may have given them some advantage in the night battle.
Some of revolutionary war accounts state that it was a hot night and partly cloudy as the Armies met under a tall canopy of widely spaced pines. The road was wide with many parallel paths in the deep white sand and no doubt, the sand gleamed under the full moon as the armies met, eight tenths of a mile north of Gum Swamp Creek. The night battle covered three-tenths of mile farther north by the time both sides pulled back. The British Army lay on the ground at one mile north of Gum Swamp. The American Army was six hundred yards north of the British.
Moon research resources: Many Moons by Diana Brueton and The Astronomical Applications Dept., U.S. Naval Observatory, Washington, DC
Source: CBB cd