They can also chart Titanic's voyage from the day it set sail on its maiden voyage from Southampton in April 1912 bound for New York.

BBC: Last Updated: Friday, 2 March 2007, 12:45 GMT

This year marks the 75th anniversary of the RMS Queen Mary's maiden voyage, when she set sail from Southampton, England to Cherbourg, France to New York for a five-day voyage in 1936.

BBC: A ghostly visit on the RMS Queen Mary hotel