The World Wildlife Fund commissioned a 2019 clean-up mission on the Baltic Sea floor and the divers made an unexpected discovery: “a colleague surfaced and said there was a fishing net with a typewriter in it,” says Florian Huber, who leads the initiative. In fact, the trapped object is an Enigma encryption machine, used by the Germans during World War II and presumably thrown overboard, in an attempt to prevent it from falling into the hands of the Allies.
During that war conflict, the Nazis used an advanced encryption system that consisted of these machines and that encrypted messages so that, if they fell into enemy hands, they could not be interpreted. The machines were equipped with rotors that allowed to encode the message differently each time the button was pressed to encrypt. The Enigma now found in Gelting Bay has three rotors, which leads researchers to suggest that it was equipping a warship and not a submarine, since they had machines with four rotors since 1942.
Conservatives at the Schleswig Holstein archaeological museum in Germany estimate that the machine found now still needs a year of cleaning and restoration before it can be displayed, reports the ArsTechnica.
The solution found by the Nazis to encode the messages was sophisticated to the point of having to change the settings of the rotors daily, following the code manual of the configurations that accompanied each unit. Alan Turing and his colleagues were able to decipher the system in 1941 and were, for the rest of the War, trying to keep up with the changes and improvements that the Nazis were making in their Enigma.