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Encounter Classification

Classification of UFO Encounters

From Hynek’s system to modern extensions of contact

Introduction: Why Classification Matters

When faced with thousands of unexplained aerial encounters around the world, researchers needed a framework. Without categories, everything from a “light in the sky” to an alleged abduction would blur together. In the 1970s, astronomer Dr. J. Allen Hynek (once a consultant for Project Blue Book) created a set of encounter types that became the standard method for classifying UFO experiences.

Hynek’s Close Encounter scale — later expanded by others — provides a shared language for researchers, experiencers, and investigators. This page outlines the key categories, their significance, and how modern encounters continue to expand the scale.

Hynek’s Classification System

Close Encounters of the First Kind (CE‑I)

UFO Sighting at Close Range

  • A visual encounter with a UFO within 500 feet.
  • Object appears structured, not just a point of light.
  • Classic “flying saucer” sighting, often with unusual movement.
  • Example: Kenneth Arnold (1947) reporting nine shimmering discs over Mount Rainier.

Close Encounters of the Second Kind (CE‑II)

Evidence Left Behind

  • UFO leaves physical traces: scorched earth, EM interference, radar tracks, physiological effects on witnesses.
  • Example: Police officer Lonnie Zamora (Socorro, 1964) — craft left burned vegetation and landing marks.

Close Encounters of the Third Kind (CE‑III)

Beings Observed

  • Witness sees “occupants” or entities associated with a craft.
  • Entities often described as humanoid or alien, ranging from Greys to “little men” in metallic suits.
  • Example: 1973 Pascagoula case — witnesses claimed robotic‑like beings emerged from an object.

Extensions Beyond Hynek

Close Encounters of the Fourth Kind (CE‑IV)

Abduction Phenomenon

  • Experiencer taken aboard a craft or transported elsewhere.
  • Involves medical exams, missing time, implants, or communication.
  • Example: Betty & Barney Hill (1961), Travis Walton (1975).

Close Encounters of the Fifth Kind (CE‑V)

Conscious Human‑Initiated Contact

  • Coined by Dr. Steven Greer — direct contact with intelligences through meditation, telepathy, light signals, or other cooperative means.
  • Example: Multiple groups worldwide practice CE‑V protocols, reporting anomalous lights during contact events.

Close Encounters of the Sixth Kind (CE‑VI)

Injury or Death

  • Proposed addition — cases where UFO encounters have resulted in serious bodily harm or fatalities.
  • Example: Brazilian soldier José S. (Colares, 1977) injured by beams of light during mass wave of “chupa‑chupa” attacks.

Close Encounters of the Seventh Kind (CE‑VII)

Hybridization / Integration

  • Suggested by researcher David Jacobs.
  • Refers to encounters involving genetic manipulation, hybrid offspring, or integration of hybrids within human society.
  • Example: Abduction accounts describing hybrid children “presented” to human parents aboard craft.

Other Systems of Classification

Vallee’s Typology (Jacques Vallée, 1972)

  • Goes beyond Hynek, cataloging cases not just by distance but by effects.
  • Examples:

    • ANOMALY (light phenomena)
    • VEHICLE (craft observed)
    • ENTITY (beings observed)
    • PHYSICAL EFFECTS (traces, burns, disruptions)
    • PSYCHIC EFFECTS (telepathy, altered perception)
    • CULTURAL EFFECTS (inspirations, cults, myths)

MODERN SCIENTIFIC CATEGORIES

Organizations now classify encounters with multi‑factor checklists:

  • Physical Evidence (materials, radiation, radar)
  • Physiological Effects (heat, burns, PTSD)
  • Psychological Effects (dreams, psychic downloads, synchronicities)
  • Environmental Effects (traces, animal reactions, EM anomalies)

Why Classification Is Important

  1. Organizing Data: Structures thousands of cases into meaningful categories.
  2. Scientific Rigor: Provides pathways for comparison and correlations.
  3. Witness Validation: Helps experiencers articulate what kind of encounter they had.
  4. Expanding the Mystery: Shows how the phenomenon evolves — from mere sightings to complex consciousness‑based interactions.

Case Studies by Classification

  • CE‑I: Phoenix Lights (1997) — thousands seeing massive triangular craft.
  • CE‑II: Rendlesham Forest (UK, 1980) — landing traces, radiation readings.
  • CE‑III: Kelly–Hopkinsville (1955) — humanoid beings surrounding farmhouse.
  • CE‑IV: Travis Walton (1975) — 5‑day abduction, witnessed by entire logging crew.
  • CE‑V: 21st century CE‑V groups reporting responsive orbs and structured lights.
  • CE‑VI: Colares, Brazil attacks with physical injuries.
  • CE‑VII: Abduction testimony of alien‑human “hybrid nurseries.”

The Bigger Picture

Classification systems reveal a spectrum: UFOs are not just aerial objects but a complex interface between technology, biology, and human consciousness. From lights in the sky to hybridization narratives, the phenomenon seems to evolve in layers of contact.

Explore Further on UFO Timeline Project

Closing Thoughts

Dr. Hynek once said, “The UFO phenomenon has nothing to do with science fiction. It is real and it demands serious scientific attention.”

The Classification of Encounters shows just how varied yet interconnected the phenomenon is. From sightings of craft to human‑initiated contact and beyond, these categories help us trace humanity’s ongoing interaction with the unknown.

The Hynek UFO encounter classification system.


Developed by Dr. J. Allen Hynek, is a framework for categorizing UFO sightings based on the nature and proximity of the encounter. Here’s an overview:

1. Nocturnal Lights

Unexplained lights seen in the night sky, often moving in ways that do not match known aircraft or natural phenomena.

2. Daylight Discs

Unidentified objects observed during the day, typically described as disc-shaped, but also including other shapes like ovals or cigars.

3. Radar-Visual Cases

UFOs detected both visually and on radar, providing corroborating evidence from two independent sources.

4. Close Encounters

These are divided into three main types, based on the proximity (within 500 feet) and the nature of the experience:

  • Close Encounter of the First Kind (CE-I):

    Visual sighting of an unidentified flying object at close range, with no interaction or physical effects.

  • Close Encounter of the Second Kind (CE-II):

    A sighting where a UFO leaves a physical effect, such as scorched ground, broken branches, electromagnetic interference, or physiological effects on witnesses.

  • Close Encounter of the Third Kind (CE-III):

    A sighting where occupants or entities associated with the UFO are seen.

Later researchers and popular culture have expanded on Hynek’s system, adding:

  • Close Encounter of the Fourth Kind:

    Abduction of a human by a UFO or its occupants.

  • Close Encounter of the Fifth Kind:

    Direct communication between humans and extraterrestrial beings.

But the original Hynek system focused on the first three close encounter types, along with the general categories of nocturnal lights, daylight discs, and radar-visual cases.

Source: UFOEvidence.org

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UFO Sightings

Visual and or radar only.

1. Nocturnal Lights (NL)

Any anomalous light(s) seen in the night sky whose description rules out the possibilities of aircraft lights, stars, meteors and the like.

2. Daylight Discs (DD)

Un-identified flying objects seen in the distant daytime sky. The UFOs classed in this category can be other shapes as well, like cigars, eggs and ovals.

3. Radar-Visual Cases (RV)

Where UFOs are tracked on radar and can be seen at the place illustrated at the same time.

Close Encounters

Encounters with NHI (Non-Human Intelligences)

4. Close Encounter of the First Kind (CE-I):

A UFO in close proximity (within approx. 500 feet) of the witness.

5. Close Encounter of the Second Kind (CE-II):

A UFO that leaves markings on the ground, causes burns or paralysis to humans, frightens animals, interferes with car engines or TV and radio reception.

6. Close Encounter of the Third Kind (CE-III):

A CEI or CEII which has visible NHI as occupants.

New Additional Close Encounters

(these are unofficial)

7. Close Encounter of the Fourth Kind (CE-IV):

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8. Close Encounter of the Fifth Kind

 (CE-V):

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9. Close Encounter of the Fifth Kind (CE-VI):

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