Observed three red asynchronous flashing lights traveling in a straight line path. Darkness seemed to indicate a triangular shape with one light in front. Lights flashed in no distinguishable pattern. The only object flew lower than most regularly observed aircraft. The sky was clear and a half moon nearly silhouetted the object. It was observed for only a few minutes before traveling out of sight. A plane was observed a few minutes later. It's engines were easily heard.