Alan Turing and the Enigma code Mystery Cache
Alan Turing and the Enigma code
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A cache in honour of Alan Turing and his work on cracking the Enigma code.
To find this GEOcache, follow the instructions to make your very own enigma machine and crack the code…
This is a puzzle cache and so you must work out the true co-ordinates of the cache. There is nothing hidden at the co-ordinates given above, and anyway only college fellows are allowed to walk on the grass here.
Background
Alan Turing studied as an undergraduate at King's College from 1931 to 1934, where he gained first-class honours in Mathematics. In 1935, at the young age of 22, he was elected as a fellow at King's.
On 4 September 1939, the day after the UK declared war on Germany, Turing reported to Bletchley Park, the wartime station of the Government Code and Cypher School. Within weeks, Turing had specified an electromechanical machine that could help break Enigma. The bombe, with an enhancement suggested by another Cambridge mathematician Gordon Welchman, became one of the primary tools, and the major automated one, used to attack Enigma-enciphered messages.
Enigma machines were used by the German military to encrypt and decrypt secret messages before and during World War II. It was considered to be close to unbreakable, and the German cryptographers behind it thought it was impossible that anyone could go to the immense effort required to do so.
It is widely quoted that decryption of German ciphers hastened the end of the European war by two years, and Winston Churchill told King George VI after World War II: "It was thanks to Ultra [the codebreaking programme] that we won the war."
To find out more, the following Wikipedia pages are a good start:
Alan Turing
Cryptanalysis of the Enigma
Enigma machine
Instructions
Make your own Enigma machine, using just a piece of paper and scissors!
- Download and print out the template from https://mckoss.com/posts/paper-enigma/ or here
- Follow the instructions to practice using it to decrypt the sample message on the sheet.
How messages were encrypted
The initial rotor settings were provided in code books to all Enigma operators. These would tell the operator the rotor order and initial position of each rotor to be used on a given date.
The three rotors (numbered I, II and III) would be inserted in the order and position specified (for example rotor order II-I-III at positions A-B-C).
The operator would then pick a three letter key “at random” for this message only, and transmit it twice to make sure it was received properly. The rotor positions would then be changed to be equal to the three letter key just transmitted, and the rest of the message would be sent.
How messages were decrypted
The Enigma machine was set to the rotor order and positions for that date from the code book. The first six letters received would be decrypted to reveal the three letters (repeated) which are the starting positions for the rest of the message.
Now try it yourself
The following message has just been intercepted and needs to be decrypted urgently:
OAEZXV Z ZA E.XPL Y T.GDA
We have a code book which was salvaged from a sinking U-boat, but the entry for today’s rotor settings are incomplete. The rotor order is known to be I-II-III but the initial rotor positions are unknown, they need to be found to decode the message.
Once you have decrypted the message a simple translation may be needed to obtain digits. Good luck!
You can check your answers for this puzzle on:
Please bring a pen and tweezers.
Congratulations to Plasadda on being FTF!
Additional Hints
(Decrypt)
Fgneg jvgu gbqnl’f ebgbe frggvatf sbe rnpu zrffntr orybj.
Punyyratvat: [UUVXUZNXNQKQUQRJVOYTCVFBCMJWNQTZLOWXZHTXW]
Rnfvre: [UMAOFVNXYQMUCORCXQX]
Treasures
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