Contact your travel agent or Celebrity (800-437-3111) for information on the Millennium-class ships, including the latest entry, Summit , which features in its alternative dining room lacquered panels from the first-class smoking room of the great French ship Normandie . The fourth and final ship, the Constellation , will hold a collection of memorabilia and artwork from a variety of ships. To celebrate the fiftieth anniversary of the launching of the SS United States on July 3, 1952, Celebrity has scheduled a special tribute during the week of Infinity ’s June 28 Alaska cruise.