The UMMO Affair

Beginning in 1966, Spanish ufologists and scientists received an extraordinary series of communications purportedly from extraterrestrial beings originating from a planet called Ummo, located 14.6 light-years from Earth. The affair would span decades, involve thousands of pages of technical documents, and include UFO sightings - before being revealed as an elaborate hoax.

The First Contact

In early 1966, Fernando Sesma, president of a Madrid-based group interested in extraterrestrial contact, began receiving typed letters claiming to be from inhabitants of planet Ummo. The letters were marked with a distinctive symbol resembling the astrological sign for Uranus: )+(

The correspondents explained they had been observing Earth since 1950, when they detected a radio signal transmitted during the Norwegian campaign of World War II. A landing party allegedly arrived in 1950 in the French Alps.

The Communications

Over the following years, recipients in Spain, France, and other countries received an estimated 1,500 pages of technical documents covering:

Science and Technology

• Detailed descriptions of Ummite physics, including their understanding of space-time
• Advanced propulsion concepts for interstellar travel
• Biological and medical knowledge
• Mathematical frameworks beyond human understanding

Philosophy and Society

• Descriptions of Ummite civilization and government
• Their moral and ethical systems
• Views on Earth’s religions and social structures
• Warnings about humanity’s self-destructive tendencies

Technical Accuracy

What made the UMMO papers remarkable was their scientific sophistication. The documents contained advanced concepts in:

• Non-Euclidean geometry
• Cosmology predating human discoveries
• Theoretical physics
• Genetics and molecular biology

Some concepts later proved consistent with subsequent scientific discoveries, while others contained obvious errors that skeptics noted were inconsistent with an advanced civilization.

The San José de Valderas Sighting

On June 1, 1967, multiple witnesses reported a UFO over the San José de Valderas suburb of Madrid. The craft allegedly displayed the UMMO symbol on its underside. Several photographs emerged showing a disc-shaped craft with the distinctive )+(marking.

Additional sightings with the UMMO symbol were reported in:

• Santa Monica, California (1967)
• Argentina (1968)
• Various locations in Spain (1970s)

The Investigation

The affair attracted serious attention from scientists and intelligence agencies:

CIA Interest

Declassified documents reveal the CIA monitored the UMMO affair, intrigued by the technical sophistication of the communications and the psychological manipulation involved.

Scientific Analysis

French physicist Jean-Pierre Petit was among researchers who took the UMMO documents seriously. He found certain concepts, particularly regarding magnetohydrodynamics and cosmology, to be ahead of contemporary human knowledge.

Linguistic Analysis

The documents contained a detailed constructed language for Ummite, with consistent grammar and vocabulary across thousands of pages - a feat requiring extraordinary effort to fabricate.

The Revelation

In 1993, José Luis Jordán Peña, a Spanish psychologist with expertise in parapsychology, confessed to creating the entire UMMO affair as a social experiment. He claimed to have:

• Written all the documents himself
• Sent them using a network of accomplices
• Faked the UFO photographs using models
• Orchestrated the sightings with co-conspirators

Jordán Peña stated his goal was to study how belief systems form and spread. However, questions remained:

• The scientific content seemed beyond one person’s expertise
• The logistical effort was immense
• Some researchers doubted his confession was complete

Legacy

The UMMO affair remains significant in UFO history:

• It demonstrated how sophisticated disinformation can spread
• It showed the hunger for extraterrestrial contact, especially during the Cold War
• The scientific documents, regardless of origin, contained genuinely novel ideas
• It influenced subsequent hoaxes and alleged contacts

Some UMMO believers refused to accept Jordán Peña’s confession, suggesting he was either a disinformation agent or one node in a larger operation. A small community of UMMO followers persists today, continuing to analyze the documents.

The affair serves as both a cautionary tale about the will to believe and a fascinating example of an elaborate, long-running hoax that fooled experts for decades.