Cracking the Zodiac Cipher: A 51-Year Mystery Solved

Liputan6.com, Jakarta For over 50 years, the Zodiac cipher remained one of the most infamous unsolved codes in history. Sent by the unidentified Zodiac Killer in 1969, the 340-character cryptogram taunted investigators and amateur sleuths for decades. But in December 2020, an international team of codebreakers finally cracked the cipher, revealing the killer's chilling message. This breakthrough captivated the public and reignited interest in the unsolved Zodiac case. Let's explore the fascinating story of how this legendary cipher was created, the many attempts to solve it over the years, and the groundbreaking techniques that finally unlocked its secrets after half a century.

The Zodiac cipher refers to a coded message sent to the San Francisco Chronicle newspaper on November 8, 1969. It was written by the unidentified serial killer known as the Zodiac Killer, who terrorized Northern California in the late 1960s. The cipher contained 340 characters made up of letters, numbers and symbols arranged in a grid.

This was actually the second cipher sent by the Zodiac Killer. His first 408-character cipher had been quickly solved in 1969 by a schoolteacher and his wife. But the 340-character cipher proved much more difficult to crack. For decades, it resisted the efforts of top cryptography experts, law enforcement, and amateur codebreakers.

The Zodiac Killer claimed the cipher contained his identity, though this turned out not to be true when it was finally solved. Instead, the decrypted message contained more of the killer's taunting and boasting. But cracking this famously difficult cipher was still considered a major achievement in the fields of cryptography and true crime investigation.

The Zodiac cipher was created by the unidentified serial killer known only as the Zodiac Killer. This mysterious criminal murdered at least five people in Northern California between December 1968 and October 1969, though he claimed to have killed many more.

The Zodiac Killer became infamous not just for his murders, but for the letters and cryptograms he sent to local newspapers. He demanded these be published on the front page or he would go on a killing spree. The killer seemed to enjoy taunting the police and public with his coded messages.

Experts believe the Zodiac likely had some knowledge of cryptography and codemaking, but was not a professional. He appeared to create his ciphers by hand rather than using any advanced techniques. The killer may have been inspired by ciphers used in wartime or those that appeared in puzzle books and magazines.

To this day, the true identity of the Zodiac Killer remains unknown, despite decades of investigation. So while we know he created the infamous 340-character cipher, the person behind it is still a mystery.

The 340-character Zodiac cipher was mailed to the San Francisco Chronicle newspaper on November 8, 1969. This was about three months after the Zodiac's previous 408-character cipher had been quickly solved.

The timing is significant because it came during the height of the Zodiac Killer's crime spree in 1969. He had committed his first confirmed murders in December 1968, killing a young couple. In 1969, he attacked two more couples and a cab driver between July and October.

The cipher arrived just a few weeks after the Zodiac's last known murder on October 11, 1969. At this point, the killer was actively taunting police through letters and phone calls. Sending this new, more complex cipher was likely another way for him to demonstrate his perceived superiority over law enforcement.

After mailing the 340-character cipher in November 1969, the Zodiac continued to send letters for several years. But the 340 cipher was his last confirmed cryptogram. Its difficulty in being solved may have satisfied the killer's desire to outsmart investigators and the public.

The Zodiac cipher was finally cracked by an international team working remotely from the United States, Australia and Belgium. The key breakthrough happened on December 3, 2020, when the team used specialized cryptography software to decipher the message.

Specifically, the codebreakers were:

• David Oranchak - A software developer in Virginia, USA
• Jarl Van Eycke - A Belgian computer programmer
• Sam Blake - An Australian mathematician

These amateur cryptography enthusiasts had been working on the Zodiac cipher for years as a hobby. They collaborated online, sharing ideas and using computers to test countless possible solutions.

Once they believed they had cracked the code, the team submitted their solution to the FBI's Cryptanalysis and Racketeering Records Unit (CRRU). After examining the work, the FBI confirmed on December 11, 2020 that the 340-character cipher had indeed been solved.

So while much of the work was done remotely by the international team, the official verification happened at FBI headquarters. The solution was then shared with the San Francisco FBI office handling the Zodiac Killer case.

The Zodiac's 340-character cipher resisted decryption for over 50 years due to several factors that made it uniquely challenging:

• Complex Encoding Method - The Zodiac used a technique called transposition, where he rearranged the order of letters after encrypting them. This added an extra layer of complexity.
• Errors in the Cipher - Whether intentional or not, the Zodiac made some mistakes in creating the cipher. This threw off many attempts to solve it systematically.
• Lack of Repetition - There were few repeating sequences of characters, which codebreakers often use to detect patterns.
• Unknown Key Length - Codebreakers didn't know how long the encryption key was, making it harder to attack.
• Unique Symbols - The Zodiac used some symbols that didn't appear in his previous solved cipher, adding uncertainty.
• Short Message Length - At only 340 characters, there wasn't much text for analysts to work with statistically.
• Expectations of Hidden Information - Many assumed the cipher contained the Zodiac's name or identity, leading them down false paths.

These factors combined to make the 340 cipher exceptionally difficult compared to the Zodiac's earlier ciphers. It required advanced computing techniques unavailable for most of its history to finally crack.

Cracking the Zodiac's 340-character cipher after 51 years required a combination of human insight, computing power, and a bit of luck. Here are the key steps that led to the breakthrough:

1. Collaboration - An international team of codebreakers joined forces, sharing ideas and techniques online.
2. Advanced Software - The team used AZdecrypt, a specialized program for solving substitution ciphers developed by Jarl Van Eycke.
3. Massive Computing Power - They ran the software on powerful computers, testing millions of possible solutions.
4. Novel Approach - The team tried splitting the cipher into three sections and rearranging the characters diagonally.
5. Pattern Recognition - The software detected promising fragments of words like "GAS CHAMBER" in some outputs.
6. Human Analysis - The codebreakers carefully examined the most promising computer outputs.
7. Refinement - They gradually pieced together more of the message, adjusting for the Zodiac's errors.
8. Verification - The full solution was checked against known facts about the Zodiac case.
9. FBI Confirmation - The team submitted their solution to the FBI, who validated it as correct.

This process combined human expertise in cryptography and the Zodiac case with cutting-edge computing techniques. It demonstrates how modern technology can help solve long-standing mysteries when applied creatively by dedicated researchers.

When the Zodiac's 340-character cipher was finally cracked in 2020, it revealed a chilling message from the killer.

I HOPE YOU ARE HAVING LOTS OF FUN IN TRYING TO CATCH ME THAT WASN'T ME ON THE TV SHOW WHICH BRINGS UP A POINT ABOUT ME I AM NOT AFRAID OF THE GAS CHAMBER BECAUSE IT WILL SEND ME TO PARADICE ALL THE SOONER BECAUSE I NOW HAVE ENOUGH SLAVES TO WORK FOR ME WHERE EVERYONE ELSE HAS NOTHING WHEN THEY REACH PARADICE SO THEY ARE AFRAID OF DEATH I AM NOT AFRAID BECAUSE I KNOW THAT MY NEW LIFE IS LIFE WILL BE AN EASY ONE IN PARADICE DEATH

Some key points about this message:

• It does not reveal the Zodiac's identity as he had claimed it would.
• He references a TV show where someone claimed to be him, saying it wasn't actually him.
• The killer expresses no fear of execution, believing he'll go to "paradice" [sic].
• He claims to have "slaves" who will serve him in the afterlife.
• The message is filled with spelling errors and some garbled text at the end.

While disappointing to those hoping for a revelation about the killer's identity, solving this long-standing cipher was still considered a major breakthrough in the case. It provided new insight into the Zodiac's thinking and confirmed his continued desire to taunt the public decades after his crimes.

Cracking the Zodiac's 340-character cipher after 51 years provided several important benefits:

• Advancing Cryptography - The techniques used to solve this cipher can help crack other complex codes.
• Cold Case Progress - While it didn't identify the killer, it eliminated dead-end theories and refocused the investigation.
• Historical Closure - Solving this famous unsolved code provided resolution to a long-standing mystery.
• Public Engagement - The breakthrough renewed public interest in the Zodiac case and codebreaking.
• Psychological Insight - The decoded message offered new glimpses into the killer's mindset.
• Collaborative Success - It showed how international teamwork and technology can solve difficult problems.
• Inspiration - The solution may encourage more people to pursue careers in cryptography and forensics.
• Victim Closure - For victims' families, solving the cipher may provide some sense of progress in the case.

While the cipher's solution didn't crack the case, it demonstrated the value of persistence in tackling seemingly impossible puzzles. It also highlighted how modern computing power can be applied to long-standing mysteries.

The Zodiac's 340-character cipher stands out among famous unsolved codes. Here's how it compares to some other well-known ciphers:

The Zodiac 340 cipher stands out for its relatively short length but long time to solve. This speaks to its complexity compared to other famous codes. Its solution required advanced computing techniques unavailable for most of its history.

The Zodiac Killer sent multiple ciphers, each with unique characteristics. Here are the key differences between them:

Zodiac 408 Cipher

• Sent in July 1969
• 408 characters long
• Solved within 1 week
• Used simple substitution method
• Contained coherent message about killing

Zodiac 340 Cipher

• Sent in November 1969
• 340 characters long
• Took 51 years to solve
• Used complex transposition method
• Message was more rambling, with errors

Zodiac 13 Cipher

• Sent in April 1970
• Only 13 characters
• Still unsolved
• Claims to contain Zodiac's name
• Too short for traditional codebreaking

Zodiac 32 Cipher

• Sent in June 1970
• 32 characters long
• Still unsolved
• Possibly related to a map
• May not be a real cipher

These differences show how the Zodiac evolved his ciphers over time, making them progressively more difficult to solve. The 340 cipher represents the peak of his cryptographic efforts.

Q: Did solving the cipher reveal the Zodiac Killer's identity?

A: No, the decrypted message did not contain any information about the killer's identity.

Q: Are there any remaining unsolved Zodiac ciphers?

A: Yes, the 13-character cipher from April 1970 and the 32-character cipher from June 1970 remain unsolved.

Q: Could modern technology solve the case now?

A: While technology helped crack the cipher, identifying the killer would likely require new physical evidence or witnesses coming forward.

Q: Why did it take so long to solve the 340 cipher?

A: Its complex encoding method and the Zodiac's errors made it resistant to traditional codebreaking techniques. It required advanced computing power not available earlier.

Q: Is the Zodiac Killer case still open?

A: Yes, the case remains open in several jurisdictions in California. The FBI also continues to assist local law enforcement with the investigation.

Q: Could the Zodiac still be alive?

A: It's possible but unlikely. If still alive, the Zodiac would likely be in his 80s or 90s now.

Q: Are there any prime suspects in the Zodiac case?

A: Many suspects have been proposed over the years, but none have been conclusively linked to the crimes. The most well-known suspect was Arthur Leigh Allen, but he was never charged.

Q: Will the remaining Zodiac ciphers ever be solved?

A: The shorter 13 and 32 character ciphers may be too brief to solve definitively. However, advances in technology could potentially crack them in the future.

The cracking of the Zodiac's 340-character cipher in 2020 marked the end of a 51-year quest. This breakthrough demonstrated the power of combining human expertise, international collaboration, and advanced computing techniques to solve seemingly impossible puzzles. While it didn't reveal the killer's identity, it provided new insights into one of America's most infamous unsolved cases.

The solution to this cipher serves as a testament to human perseverance and ingenuity. It shows that even decades-old mysteries can potentially be unraveled with the right combination of dedication and technology. As we look to the future, the techniques used to crack the Zodiac cipher may help solve other complex codes, both in criminal investigations and other fields.

The Zodiac case continues to captivate the public imagination, blending elements of true crime, cryptography, and unsolved mystery. While the identity of the killer may never be known, the solving of his most infamous cipher ensures that this case will be remembered not just for its brutality, but also for the relentless pursuit of truth that it inspired.