United States lightship Nantucket (LV-112), also known as Lightship No. 112, Nantucket, is a National Historic Landmark lightship that served at the Lightship Nantucket position. She was the last serving lightship and at time of its application as a landmark, one of only two capable of moving under their own power. She served as the lightship for such notable vessels as SS United States, RMS Queen Mary, and SS Normandie.