When was the the ship launched ,that along with the Tripitz and the Lützow was a target for  Operation Source ?
Operation Source Operation Source was a series of attacks to neutralise the heavy German warships – "Tirpitz", "Scharnhorst" and "Lützow" – based in northern Norway, using X-class midget submarines.
German submarine U-2355 German submarine "U-2355" was a Type XXIII U-boat of Nazi Germany's "Kriegsmarine" during World War II. She was ordered on 20 September 1944, and was laid down on 18 October 1944 at Deutsche Werft AG, Hamburg, as yard number 509. She was launched on 13 December 1944 and commissioned under the command of "Oberleutnant zur See" Hans-Heino Franke on 12 January 1945.