Confronting UnknownsGlossary

Confronting Unknowns: Glossary

A reference for the terms, agencies, sensors, and methods in the paper.

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209 terms

A

A5712: New Jersey Assembly Bill 5712, signed January 12, 2026, by Governor Phil Murphy as P.L. 2025, c.269. Establishes a state Center for the Study of Unidentified Aerial Phenomena with approximately $3.5 million in appropriations, including $2.5 million in research grants.
AARO: All-domain Anomaly Resolution Office. U.S. Department of Defense office established in 2022 to investigate UAP across air, sea, space, and transmedium domains; reports through ODNI channels and issues annual consolidated reports to Congress.
AATIP: Advanced Aerospace Threat Identification Program. Pentagon office that studied anomalous aerospace events from 2007 to 2012 with approximately $22 million in funding; publicly revealed by the *New York Times* in December 2017.
AAWSAP: Advanced Aerospace Weapon System Applications Program. Defense Intelligence Agency program (2008–2010) that preceded AATIP, contracted to Bigelow Aerospace and producing the DIRD technical report series on advanced propulsion and related topics.
ADS-B: Automatic Dependent Surveillance–Broadcast. Cooperative surveillance technology in which aircraft broadcast position, altitude, velocity, and identity via transponder. Objects detected on radar but absent from ADS-B feeds are common candidates for further investigation.
AESA: Active Electronically Scanned Array. A phased-array radar architecture on modern fighter aircraft including the AN/APG-77 (F-22) and AN/APG-79 (F/A-18E/F), enabling rapid beam steering and simultaneous multi-target tracking.
AFGSC: Air Force Global Strike Command. U.S. Air Force major command headquartered at Barksdale AFB, responsible for the bomber leg of the nuclear triad and most U.S. ICBM forces.
AI: Artificial intelligence. Systems performing tasks that typically require human cognition, including perception, reasoning, and classification. In CU26, AI refers primarily to machine-learning and multimodal LLM systems used for sensor-data triage, anomaly detection, and probabilistic identification.
AIM-9X: Air Intercept Missile 9X "Sidewinder." Short-range infrared-guided air-to-air missile carried by U.S. and allied fighters; cited in escalation-ladder discussions of intercept options.
AIS: Automatic Identification System. Global vessel-tracking transponder system used in maritime surveillance; relevant for ruling out ship misidentification in coastal and over-water UAP events.
AN/APG-77: The AESA radar carried by the F-22 Raptor. Provides long-range air-to-air detection and tracking with low-probability-of-intercept characteristics.
AN/APG-79: The AESA radar carried by the F/A-18E/F Super Hornet. Provides simultaneous air-to-air, air-to-ground, and electronic-warfare functions.
Anchoring: A cognitive bias in which decision-makers weight a first plausible explanation too heavily, biasing subsequent analysis. Identified in the CU26 Crisis Playbook as a decision trap to be checked through structured workflow gates.
Antwerp incursion: Reported drone incursion over the Belgian port of Antwerp during the November 2025 Belgian drone wave; Belgium announced plans to install an air-defence system at the port by 2027.
Article 4: The provision of the North Atlantic Treaty allowing any NATO member to request consultations when its territorial integrity, political independence, or security is threatened. Invoked by Estonia in September 2025 after Russian MiG-31 airspace violations.
Artifact (H1): The CU26 explanatory hypothesis attributing an apparent event primarily to sensor behavior, processing error, or interpretation failure (e.g., parallax, lens flare, radar multipath). The paper treats H1 as an explicit top-level hypothesis rather than a report attribute.
ASRS: Aviation Safety Reporting System. Confidential, voluntary reporting system administered by NASA for the FAA, processing approximately 100,000 pilot and ATC reports per year.
Asymmetric Warfare Group: A former U.S. Army unit (2006–2021) providing operational advice on irregular and emerging threats; alumni include the retired Army counter-UAS specialist whose offered expertise during the New Jersey incident was declined.
ATFLIR: Advanced Targeting Forward-Looking Infrared. Targeting pod on U.S. Navy aircraft providing infrared imagery; source of several widely circulated UAP videos.
Atomic Energy Act: U.S. statute (1954, as amended) governing the development, regulation, and disposition of atomic energy and nuclear materials; classifies certain weapons-design and reactor information as "Restricted Data." Cited in CU26 alongside the Invention Secrecy Act and ITAR/EAR as one regime potentially applicable to breakthrough technologies derived from UAP study.
Authority bias: A cognitive bias in which decision-makers defer to the highest-ranking voice in a room rather than the best-informed one. Identified in the CU26 Crisis Playbook as a decision trap.
Availability bias: A cognitive bias in which the most recent, vivid, or dramatic explanation is weighted disproportionately. Identified in the CU26 Crisis Playbook as a decision trap.
AWACS: Airborne Warning and Control System. The E-3 Sentry aircraft providing long-range airborne radar, command and control, and battle management; cited in the Langley response as a platform deployed against the unidentified incursions.

B

B61: The B61 family of low-yield U.S. tactical nuclear gravity bombs. Referenced in nuclear-asset and force-protection contexts associated with bases experiencing drone incursions.
Baltic Sentry: NATO maritime mission launched in January 2025 to protect undersea cables, telecom links, and pipelines in the Baltic Sea following damage to seabed infrastructure.
Bardufoss: Norwegian Air Force station and civil airport in Troms; reported flight disruptions linked to drone sightings during the September 2025 Denmark drone wave.
Barksdale AFB: U.S. Air Force base in Bossier Parish, Louisiana, home to the 2nd Bomb Wing (B-52H) and headquarters of Air Force Global Strike Command. Experienced unauthorized drone incursions beginning March 9, 2026.
Bayesian inference: A statistical method in which prior probabilities for a set of hypotheses are updated to posterior probabilities as new evidence arrives, using Bayes' theorem. In the CUF, the mechanism for ranking the H1–H5 hypotheses as sensor data, contextual information, and expert analysis accumulate.
Berlin Brandenburg Airport: Germany's principal Berlin-area international airport (BER); briefly suspended takeoffs and landings on October 31–November 2, 2025 after an unknown object was reported near a Bundeswehr (German military) helicopter hangar, and again for nearly two hours after a late-evening drone sighting.
Blue Book: See *Project Blue Book*.
Bremen Airport: German civil airport in Bremen; temporarily suspended takeoffs and landings on November 2, 2025 after a drone was spotted nearby, with at least one flight allegedly prevented.
Brønnøysund: Norwegian coastal airport; subject of an Avinor-confirmed drone observation inside the restricted zone on September 28–29, 2025 during the Denmark drone wave.
Brussels Airport: Belgium's principal international airport (BRU); repeatedly closed during the November 2025 Belgian drone wave, including more than 50 cancellations on November 4 and roughly 500 passengers overnighting in the terminal.
BVLOS: Beyond Visual Line of Sight. The capability of an unmanned system to operate beyond direct visual contact with its operator; a regulatory and detection challenge for civilian and counter-UAS authorities.

C

C-17: The C-17 Globemaster III strategic airlifter. Cited in the December 2024 Stewart Airport incident in which an unauthorized UAS approached within 25–50 feet of a C-17.
C-UAS: Counter-Unmanned Aircraft Systems. Sensors, effectors, and procedures designed to detect, track, identify, and neutralize unauthorized drones. Federal C-UAS authority in the United States is concentrated at DOJ and DHS, with expansion proposals pending.
C2: Command and control. The systems, processes, and authorities through which commanders direct forces; "C2 links" denote the radio data path between a drone and its operator.
Camp Pendleton: Marine Corps Base in Southern California; confirmed six UAS airspace entries between December 9–15, 2024.
Church Committee: The U.S. Senate Select Committee to Study Governmental Operations with Respect to Intelligence Activities, chaired by Senator Frank Church (1975–1976). Cited in CU26 as a precedent model for congressional accountability hearings preceding any future UAP disclosure.
CIA: Central Intelligence Agency. U.S. foreign intelligence service established 1947; convened the Robertson Panel in 1953, whose recommendations shaped seven decades of UAP information management.
CISA: Cybersecurity and Infrastructure Security Agency. Operational component of DHS established 2018 with responsibility for protecting U.S. critical infrastructure from cyber and physical threats.
Clarke's Third Law: Arthur C. Clarke's aphorism that "any sufficiently advanced technology is indistinguishable from magic." Invoked in CU26 to underscore that the boundary between classified or advanced human technology and genuinely unexplained phenomena is not static.
Class A–D events: Tearsheet taxonomy of anomalous airspace event severity tiers used in the Crisis Playbook framing, from routine airspace anomaly (D) to multi-domain national-security event (A).
Compartmentalization: The intelligence-community practice of restricting access to classified information by program-specific clearance ("special access program," SAP). Cited in CU26 in connection with classified UAP-relevant programs and disclosure governance.
Condon Report: *Scientific Study of Unidentified Flying Objects* (1968), authored by Edward U. Condon at the University of Colorado under USAF contract. Its conclusion that further study was unlikely to yield major scientific advances led to the closure of Project Blue Book in 1969.
CONOPS: Concept of Operations. A user-oriented description of how a system will be operated, used to derive engineering and integration requirements; CU26 recommends a CONOPS for spectral sensing on UAP-relevant aerial platforms.
Copenhagen Airport: Denmark's principal international airport; closed for nearly four hours on September 22, 2025 after multiple drone sightings, marking the opening of the European "Denmark" drone wave.
Counter-UAS: (C-UAS) Systems designed to detect, track, identify, and neutralize unauthorized unmanned aerial systems.
CRS: Congressional Research Service. Nonpartisan public-policy research arm of the U.S. Congress within the Library of Congress.
CUF: Confronting Unknowns framework. The analytical pipeline proposed in this paper, organized as Detect → Identify → Respond → Explain (D-I-R-E), with explicit feedback loops between stages.

D

D-I-R-E: The four-stage Confronting Unknowns pipeline: Detect (capture and preserve evidence), Identify (translate evidence into ranked probabilistic hypotheses), Respond (decide and act under uncertainty), Explain (communicate to operational, legislative, and public audiences).
DARPA: Defense Advanced Research Projects Agency. The U.S. Department of Defense agency funding high-risk research in emerging technologies, established 1958. Cited in CU26 as a potential sponsor for novel detection and identification research.
Decision trap: A predictable cognitive failure mode under time pressure. The CU26 Crisis Playbook explicitly identifies four: premature closure, authority bias, availability bias, and anchoring.
Denmark drone wave: The September–November 2025 sequence of unidentified-drone incidents at Copenhagen, Aalborg, Kastrup, and other Danish, Norwegian, German, Belgian, and Dutch airports and military installations. Triggered Denmark's NATO consultations and the EU "drone wall" proposal.
DHS: Department of Homeland Security. U.S. federal department established 2002 with responsibility for domestic security, including critical-infrastructure protection, counter-UAS authority, and FEMA oversight.
DIAL: Differential Absorption LIDAR. Laser remote-sensing technique probing the atmosphere for specific chemical species, with potential application to ionization-trail and propulsion-byproduct detection.
Disclosure Act: See *UAPDA*.
Disinformation: The deliberate creation and dissemination of false information intended to mislead, as distinguished from misinformation (false but not deliberately so) and malinformation (true information shared maliciously out of context).
DoD: Department of Defense. The U.S. executive department overseeing the armed forces, intelligence components within those services, and acquisition activity, including UAP-related sensing assets and AARO.
DOE: Department of Energy. U.S. federal department with responsibilities including nuclear weapons stewardship; cited in CU26 in the context of the "loose nuke" narrative around the New Jersey drone wave, which DOE and NNSA denied.
Doel nuclear power plant: Belgian nuclear generating station near Antwerp; five drones were reported circling the plant for roughly an hour during the November 2025 drone wave, prompting Belgium to request allied assistance.
DOJ: Department of Justice. U.S. federal executive department for law enforcement; holds primary federal counter-UAS authority alongside DHS.
Drone wall (EU): A European Union proposal, backed by EU leaders on October 1, 2025, to build a coordinated counter-drone perimeter along the eastern flank in response to the Denmark drone wave and Russian airspace violations.
DSCA: Defense Support of Civil Authorities. The DoD framework under which military forces support domestic civil authorities during emergencies (e.g., FEMA-led disaster response); referenced in ICS/NIMS scaling discussions.

E

EAR: Export Administration Regulations. U.S. Department of Commerce regulations controlling the export of dual-use goods, software, and technology. Cited in CU26 alongside ITAR and the Atomic Energy Act as an export-control regime potentially applicable to UAP-derived technologies.
Earle: Naval Weapons Station Earle in Colts Neck, NJ; confirmed multiple UAS airspace entries on December 13, 2024.
Eastern Sentry: NATO mission launched September 2025 to reinforce the alliance's eastern flank after Russian drones violated Polish airspace and Russian MiG-31s entered Estonian airspace. Companion mission to Baltic Sentry.
Eindhoven Airport: Dutch civil-military airport in the southeastern Netherlands; suspended air traffic for several hours in November 2025 after multiple drone sightings, prompting the Netherlands to procure drone-detection radars.
Elsenborn: Belgian Army training-area and military base in the eastern cantons; site of drone sightings that opened Belgium's military-base wave in late October 2025.
EO: Electro-Optical. Sensors operating in the visible and near-infrared spectrum; includes standard cameras and telescope systems.
EO/IR: Electro-Optical / Infrared. Combined visible-band and infrared imaging sensor package; the standard fused payload on military targeting pods, surveillance aircraft, and counter-UAS platforms.
Erding: Bundeswehr air base near Munich, Germany; site of confirmed drone sightings on October 2–4, 2025, alongside operational disruption at Munich Airport.
Escalation ladder: A graduated sequence of community or institutional responses from passive observation through interception to neutralization. Documented in CU26's New Jersey case as a predictable consequence of an information vacuum.

F

F-22: F-22 Raptor air-superiority fighter operated by the U.S. Air Force, carrying the AN/APG-77 AESA radar. Used to shoot down the Chinese surveillance balloon in February 2023 and reportedly relocated during the December 2023 Langley incursions.
F-35: F-35 Lightning II multirole stealth fighter operated by the U.S. and allies, with a fused EO/IR sensor suite (DAS, EOTS); cited in CU26 as not optimized for material identification despite advanced sensor integration.
F/A-18: F/A-18 Hornet and F/A-18E/F Super Hornet carrier-based multirole fighters operated by the U.S. Navy; carry the ATFLIR pod and AN/APG-79 radar that produced several widely circulated UAP videos.
FAA: Federal Aviation Administration. U.S. agency within the Department of Transportation responsible for civil aviation regulation, airspace management, and temporary flight restrictions (TFRs).
FBI: Federal Bureau of Investigation. U.S. domestic intelligence and law-enforcement agency within DOJ; opened public tiplines and coordinated investigative activity during the New Jersey drone wave.
FCC: Federal Communications Commission. Independent U.S. agency regulating interstate and international communications by radio, television, wire, satellite, and cable. Cited in CU26 as one of the technology-risk-governance institutions relevant to anomalous-phenomena research and spectrum management.
FEMA: Federal Emergency Management Agency. Operational component of DHS responsible for federal disaster response, NIMS administration, and coordination with state emergency-management agencies.
Fifteen Minutes to Decide: The CU26 Crisis Playbook framing: a tool set for senior decision-makers facing an anomalous airspace incident within a 15-minute decision window, covering situation classification, contact protocols, decision-trap awareness, and graduated response options.
FLIR: Forward-Looking Infrared. A category of infrared imaging sensors mounted forward on aircraft and ground platforms for thermal imaging; also the company name (now Teledyne FLIR) producing many such systems including the Boson 640 LWIR core used by the Galileo Project.
FOCI: Foreign Ownership, Control, or Influence. The regulatory determination of whether foreign entities can direct or influence a U.S. company's decisions, triggering mitigation requirements before access to classified programs.
FOIA: Freedom of Information Act. U.S. federal statute (1966) providing public access to federal agency records subject to enumerated exemptions; the primary statutory tool for declassification requests on UAP-related material.

G

Galileo Project: Harvard-based scientific UAP research initiative led by Avi Loeb, operating multi-modal ground-based observatories with FLIR Boson LWIR arrays, passive multistatic radar, RF spectrum analyzers, and acoustic and geophysical sensors. Three observatories operational in MA, PA, and NV as of early 2026.
Gatwick incident: A December 19–21, 2018 closure of Gatwick Airport (UK's second-busiest) for roughly 36 hours due to repeated drone sightings; described by airport leadership as "highly targeted." A precedent for the airport-disruption pattern of subsequent waves.
Ge-68: Germanium-68, a radioactive isotope used in medical imaging calibration. A Ge-68 pin source lost in NJ-area transit on December 2, 2024 seeded the "loose nuke / dirty bomb search" theory of the drone wave; the source was subsequently recovered.
Geran-2: The Iranian-designed, Russian-produced Shahed-136 loitering munition under its Russian designation. Cited in the Russia–Ukraine war context that backgrounded European drone-wave attribution debates.
GIMBAL: One of the three U.S. Navy F/A-18 ATFLIR videos officially released by the DoD in 2020, showing an unidentified object exhibiting unusual rotation.
GNSS: Global Navigation Satellite System. The umbrella term for satellite-based positioning and timing systems including GPS (U.S.), GLONASS (Russia), Galileo (EU), and BeiDou (China); used for precision time synchronization in sensor networks.
GOES: Geostationary Operational Environmental Satellite. NOAA's geostationary satellite constellation providing continuous 16-band visible and infrared imaging of the Western Hemisphere at 5–15 minute cadence.
GoFast: One of the three U.S. Navy F/A-18 ATFLIR videos officially released by the DoD in 2020, showing an unidentified object tracked at low altitude over the ocean.
Gothenburg-Landvetter Airport: Sweden's second-busiest airport, on the country's west coast; observed one or more drones on November 6, 2025, forcing more than a dozen flights to reroute or cancel. Swedish police opened a "suspected aviation sabotage" investigation.
GPS: Global Positioning System. The U.S.-operated GNSS constellation providing geolocation and precise time; a frequent target of jamming and spoofing in contested environments.
Gremlin: An AARO sensor system developed by the Georgia Tech Research Institute, integrating long-range EO/IR cameras, 2D/3D radar, RF spectrum monitors, and ADS-B receivers. Tested March 2024 and deployed November 2024 to an undisclosed national-security site for 90-day baseline data collection.

H

H.654: Vermont House Bill H.654, introduced 2026 by Representative Troy Headrick. Would create a state airspace-safety and UAP task force to evaluate reports, assess risks, and coordinate scientific investigation.
H1: The CU26 Hypothesis 1: Data or Sensor Artifact. The apparent event is primarily a product of sensor behavior, processing error, or interpretation failure.
H1–H5: The five top-level explanatory hypotheses in the CU26 identification taxonomy: H1 (artifact), H2 (natural), H3 (unclassified technology), H4 (classified technology), H5 (unknown). See individual H1, H2, H3, H4, H5 entries above.
H2: The CU26 Hypothesis 2: Natural Physical Source. The event reflects a known atmospheric, astronomical, oceanic, or geophysical phenomenon (e.g., birds, ball lightning, meteors, mirage).
H3: The CU26 Hypothesis 3: Human-Made Physical Source (unclassified). The event reflects a real object consistent with conventional or commercially accessible technology (e.g., drone, balloon, satellite, crewed aircraft).
H4: The CU26 Hypothesis 4: Human-Made Physical Source (classified). The event reflects a real object associated with restricted state or defense activity, including allied or adversary test programs.
H5: The CU26 Hypothesis 5: Unknown Physical Phenomenon. The event involves a real physical phenomenon not adequately explained by H1–H4; the residual unknown after artifact, natural, and human-technology hypotheses have been adequately tested.
HB 5422: Connecticut House Bill HB 5422, introduced 2026 by Representative Aundre Bumgardner. Would commission a state study of UAP in conjunction with law enforcement and state agencies to assess the feasibility of a state UAP center.
HR 8197: Federal bill introduced April 2026 by Representative Tim Burchett (R-TN). Would terminate AARO, redistribute its functions across existing Pentagon departments, and prohibit creation of any future centralized UAP office.
Human Observer: In the CU26 credibility rating scale, one of five tiers from military-trained observer (rating 1) through untrained observer in poor conditions (rating 5), with hoaxer or confirmed-fabrication actors at rating 0.
Hynek classification: The 1972 civilian and academic system developed by J. Allen Hynek classifying UFO encounters as nocturnal lights, daylight discs, radar-visual, or close encounters of the first, second, and third kinds. Predecessor to modern operational taxonomies.
Hyperspectral imaging: Imaging that captures reflectance or emission across many narrow contiguous spectral bands, enabling identification of material classes (metals, polymers, composites) through their surface signatures. Typically operates from approximately 400 to 2,500 nm.

I

ICS: Incident Command System. The standard U.S. framework for organizing multi-agency emergency response, defining roles for command, operations, planning, logistics, finance, and public information. CU26 argues that drone waves require clearer ICS triggers.
IGRA: Integrated Global Radiosonde Archive. NOAA archive of vertical atmospheric profiles from more than 2,800 stations worldwide, useful for correlating weather-balloon launches with UAP reports and assessing radar propagation anomalies.
Invention Secrecy Act: U.S. statute (1951) authorizing the federal government to impose secrecy orders on patent applications whose disclosure would be detrimental to national security. Cited in CU26's technology-governance discussion as one regime potentially applicable to UAP-derived discoveries.
IR: Infrared. Electromagnetic radiation with wavelengths longer than visible light. Subdivided into bands of increasing wavelength, VNIR, SWIR, MWIR, and LWIR, where different sensor technologies apply.
ISAR: Inverse Synthetic Aperture Radar. A radar imaging technique exploiting target motion to generate high-resolution shape and structural images, in contrast to SAR which exploits platform motion.
ISR: Intelligence, Surveillance, and Reconnaissance. Military operations and capabilities for gathering and analyzing information on adversary forces, activity, and environment.
ITAR: International Traffic in Arms Regulations. U.S. State Department regulations controlling the export and import of defense articles and services on the United States Munitions List. Cited in CU26 alongside EAR and the Atomic Energy Act as an export-control regime applicable to potential breakthrough technologies.

J

JIC: Joint Information Center. The ICS-defined entity coordinating public information across agencies during a multi-jurisdiction incident; absent during the New Jersey drone response.

K

Kastrup: Kastrup Air Base in Denmark, a Royal Danish Air Force facility co-located with Copenhagen Airport; experienced drone sightings during the September 2025 wave.
Kinematics: The description of an object's motion (position, velocity, acceleration, heading) independent of the forces producing it; in CU26, the sensor-derived motion record used to characterize candidate UAP events.
Kleine Brogel Air Base: Belgian Air Component base in Limburg; host facility for U.S. B61 tactical nuclear weapons under NATO nuclear sharing. Site of unidentified-drone activity for three consecutive nights in November 2025, which Defence Minister Theo Francken described as a deliberate spy operation.

L

Langley AFB: Joint Base Langley-Eustis, Virginia; home to the Air Force's first fighter wing. Experienced sustained nighttime UAS incursions over approximately 17 days in December 2023, prompting temporary relocation of F-22s to NAS Oceana.
LIDAR: Light Detection and Ranging. Active laser remote sensing providing high-resolution range, 3D geometry, and (in DIAL configurations) atmospheric chemical detection.
Liège Airport: Belgian cargo-and-passenger airport; repeatedly disrupted by drone sightings during the November 2025 Belgian drone wave alongside Brussels Airport.
Likelihood: In Bayesian inference, the probability of the observed evidence given a particular hypothesis. Combined with the prior probability via Bayes' theorem to produce the posterior.
LLM: Large Language Model. A class of AI models trained on large text corpora capable of natural-language understanding and generation; CU26 discusses LLM-based normalization of heterogeneous UAP reports and uncertainty summarization.
LSST: Legacy Survey of Space and Time. The decade-long primary survey program of the Vera C. Rubin Observatory, imaging the entire visible sky every three nights across six optical bands; full operations expected 2026.
LWIR: Long-Wave Infrared. The 8–14 μm thermal-emission band; the primary band for passive thermal imaging independent of illumination.

M

Marche-en-Famenne: Belgian Army garrison in Wallonia; site of drone sightings investigated by Belgian authorities in late October 2025. Defence Minister Theo Francken stated the incidents were the work of skilled operators, not amateurs.
MECE: Mutually Exclusive and Collectively Exhaustive. A property of a hypothesis set in which categories do not overlap and no possibility is excluded; the design constraint applied to the CU26 H1–H5 taxonomy.
Micro-Doppler: Fine-grained modulations of a radar return produced by component motion (rotor blades, propeller, vibration). Used in modern counter-drone radar to discriminate between birds, rotary-wing drones, helicopters, and other low-RCS targets.
MiG-31: Mikoyan MiG-31 "Foxhound" Russian high-speed interceptor. Three MiG-31s violated Estonian airspace for approximately 12 minutes in September 2025, prompting Estonia's NATO Article 4 consultations.
ML: Machine Learning. Subset of artificial intelligence in which algorithms improve performance through exposure to data rather than explicit programming.
MM-LLM: Multimodal Large Language Model. An AI model integrating text with visual and other modalities, enabling reasoning over images, sensor plots, and structured data alongside natural language; central to CU26's AI-for-anomalies discussion.
MUFON: Mutual UFO Network. Civilian organization founded in 1969 maintaining a public database of more than 140,000 UFO/UAP case reports; the principal informal reporting channel through decades of federal disengagement.
Multipath: A radar artifact in which a signal reaches the receiver via more than one path (typically a direct return plus a ground- or surface-reflected return), producing apparent ghost targets. Listed as an H1 candidate in CU26.
Munich Airport: Germany's second-busiest airport (MUC); operations disrupted on two consecutive nights, October 2–4, 2025, after drone sightings, cancelling and diverting flights affecting thousands of passengers.
MWIR: Mid-Wave Infrared. The 3–5 μm spectral band; well suited to detecting hot engine components and exhaust plumes against cooler backgrounds.

N

NAS Oceana: Naval Air Station Oceana, Virginia; cited as the temporary relocation site for F-22s during the December 2023 Langley incursions.
NASA: National Aeronautics and Space Administration. U.S. civil space and aeronautics agency established 1958; administers ASRS for the FAA and commissioned the 2023 UAP Independent Study Team Report.
NEXRAD: Next-Generation Radar. A network of 160 S-band Doppler weather radars operated jointly by the NWS, FAA, and USAF, with publicly archived reflectivity, velocity, and spectrum-width products.
Nightcrawler: An electro-optical citizen-science detection system deployed by the Tedesco brothers off Long Island and during the New Jersey drone wave, sharing data with law enforcement and journalists; subject of academic publication and a 2025 *MIT Technology Review* feature.
Nimitz incident: A November 2004 series of encounters between U.S. Navy F/A-18s from the USS *Nimitz* carrier strike group and unidentified objects ("Tic Tacs") off the coast of Southern California; one of the canonical modern U.S. military UAP cases.
NIMS: National Incident Management System. The U.S. national framework, administered by FEMA, that standardizes preparedness and response across federal, state, tribal, and local agencies; ICS is one of its core components.
NIST: National Institute of Standards and Technology. U.S. Department of Commerce agency setting measurement standards and technology guidelines. Cited in CU26 among the technology-risk-governance institutions relevant to scientific investigation of anomalous phenomena.
NJDEP: New Jersey Department of Environmental Protection. Cited in connection with the "loose nuke" radioactive-material narrative that NJDEP and federal officials publicly refuted.
NNSA: National Nuclear Security Administration. Semi-autonomous DOE agency responsible for the U.S. nuclear weapons stockpile; denied the loose-nuke search theory of the New Jersey drone wave.
NOAA: National Oceanic and Atmospheric Administration. U.S. scientific and regulatory agency within the Department of Commerce operating the NWS, NEXRAD, GOES, and the IGRA archive.
NORAD: North American Aerospace Defense Command. U.S.–Canadian joint command responsible for aerospace warning, aerospace control, and maritime warning of North America. Tracked and shot down the February 2023 Chinese surveillance balloon and three additional unidentified objects.
NORTHCOM: U.S. Northern Command. The unified combatant command responsible for homeland defense of North America; cited in CU26 in connection with radar and counter-drone reforms following Langley.
NRC: Nuclear Regulatory Commission. Independent U.S. federal agency regulating commercial nuclear power, materials, and waste; received the Palo Verde incursion reports and the December 2024 Ge-68 source-loss event report.
NSC: National Security Council. The White House body coordinating national-security policy across federal agencies. CU26's Tier 1 recommendation directs the NSC to develop and exercise interagency protocols for anomalous aerospace incursions.
NSF: National Science Foundation. Independent federal agency funding basic research and education across non-medical scientific disciplines; identified in CU26 as a potential sponsor of a dedicated UAP research funding category.
NWS: National Weather Service. NOAA component operating U.S. weather observation and forecasting systems, including NEXRAD.

O

Observer Education Feedback Loop: The CU26 mechanism by which systematic public explanation of resolved UAP cases improves observer calibration, raising the signal-to-noise ratio of incoming reports and sharpening the residual unexplained set.
ODNI: Office of the Director of National Intelligence. U.S. office overseeing the 18-member Intelligence Community, established 2004; AARO and the predecessor UAPTF reported through ODNI channels.
OHSP: Office of Homeland Security and Preparedness (New Jersey). State-level homeland-security office that co-issued the December 2024 public tipline request with FBI Newark and the New Jersey State Police.

P

Palo Verde: Palo Verde Nuclear Generating Station, Arizona; experienced multiple unidentified UAV incursions on September 29–30, 2019, prompting an inter-agency investigation that closed without identifying operators.
PEMA: Pennsylvania Emergency Management Agency. State emergency-management agency whose director discussed UAP tracking at a February 2024 budget hearing referenced in CU26.
Phoenix Lights: A mass-witness UAP event on March 13, 1997, over Phoenix, Arizona, in which a large V-shaped formation of lights traversed the city; cited in CU26 as a pre-social-media case that took weeks to reach national awareness.
Picatinny Arsenal: U.S. Army installation in Morris County, New Jersey, specializing in armaments R&D. Site of the November 13, 2024 opening incidents of the New Jersey drone wave.
Plant 42: Air Force Plant 42 in Palmdale, California, a government-owned advanced-aerospace facility associated with B-21 and other classified programs; experienced drone incursions on August 2–9, 2024.
Posterior probability: In Bayesian inference, the updated probability of a hypothesis after observing new evidence; the output of Bayes' theorem combining prior and likelihood. The CU26 H1–H5 ranking is a set of posteriors.
Premature closure: A decision trap in which an investigator declares a case resolved before evidence supports the conclusion ("it's just drones") in order to terminate analysis and public pressure. The defining failure mode in CU26's New Jersey case study.
Prior probability: In Bayesian inference, the probability assigned to a hypothesis before observing event-specific evidence. In UAP identification, priors reflect contextual factors such as proximity to military test ranges, atmospheric conditions, or known traffic patterns.
Project Blue Book: U.S. Air Force program (1952–1969) that collected and analyzed more than 12,000 UFO reports under USAF's Air Technical Intelligence Center and successors; closed following the Condon Report.
Project Galileo: See *Galileo Project*.
Project Grudge: U.S. Air Force UFO investigation program (1949–1951), successor to Project Sign and predecessor to Project Blue Book; characterized by an explicit debunking orientation.
Project Sign: The first official U.S. Air Force UFO investigation program (1947–1949), prompted by the Kenneth Arnold sighting and the early postwar wave.

R

RAF Lakenheath: Royal Air Force base in Suffolk, England, hosting U.S. Air Forces in Europe (USAFE) units; experienced UAS incursions beginning November 20, 2024.
Ramstein: Ramstein Air Base in Germany, headquarters of USAFE; experienced unidentified-drone sightings in early December 2024.
RCS: Radar Cross-Section. A measure of how detectable an object is by radar, expressed in square meters and dependent on size, shape, and material. Modern counter-drone radars focus on the low-RCS regime where small, irregular targets dominate.
Remote ID: The FAA rule requiring most drones in U.S. airspace to broadcast identification and location information; CU26 recommends fusing Remote ID with ADS-B, weather, and 911-call data in a universal operational picture.
Respond (CU): The third stage of the CUF, in which decision-ready outputs (ranked hypotheses, residual uncertainty, supporting evidence) are translated into action under rules of engagement, airspace authorities, and interagency coordination.
RF: Radio Frequency. Electromagnetic spectrum used for communication and radar; RF emissions from unidentified objects are a key detection modality.
Robertson Panel: CIA-convened classified scientific review (January 1953) of UFO reports following the 1952 Washington, D.C. incidents. Its recommendation of a media and academic debunking campaign established the stigma architecture cited throughout CU26 Part III.
Roswell: The July 1947 recovery of unidentified debris near Roswell, New Mexico. The U.S. Army Air Field's initial "flying disc" press release was retracted the following day in favor of a weather-balloon explanation; CU26 cites the announce–retract–refuse pattern as the template for subsequent communication failures.
Rubin Observatory: See *LSST*.

S

SACEUR: Supreme Allied Commander Europe. NATO's senior military commander; referenced in alliance-level escalation discussions.
Safe Airspace for Americans Act: Proposed federal legislation addressing operational response authorities for anomalous airspace incursions.
SAFER SKIES Act: 2025 federal legislation expanding the 2018 counter-UAS framework by allowing certified state and local officials to conduct approved counter-drone operations, creating a federal certification system and $250 million per year in funding for at least two years.
SAR (radar): Synthetic Aperture Radar. Radar imaging that exploits platform motion to achieve high cross-range resolution; used in satellite-based maritime surveillance and terrain mapping. Distinct from ISAR.
Schiphol Airport: Amsterdam's principal international airport; closed one runway for 45 minutes in late September 2025 after a suspected-drone sighting during the Denmark drone wave.
SCU: Scientific Coalition for UAP Studies. U.S.-based nonprofit research organization convening academic and technical UAP work; CU26 cites a 2025 Galileo Project talk delivered at SCU on foundation-model approaches to UAP sensor data.
Sensor failure mode: A class of non-physical apparent detection produced by errors (hardware, calibration), artifacts (cosmic-ray hits, lens flare, compression), interference (weather, EMI, clutter), jamming, or spoofing. The CUF requires first-pass assessment against these modes for any anomalous detection.
SIGINT: Signals Intelligence. Intelligence derived from intercepted electronic signals and communications; "passive RF / SIGINT" is one of the sensor modalities surveyed in CU26 Appendix D.
Six observables: The set of characteristics used in U.S. policy discussions (including the UAP Disclosure Act) to identify UAP-like events: instantaneous acceleration absent apparent inertia; hypersonic velocity absent a thermal signature or sonic shockwave; transmedium travel; positive lift contrary to known aerodynamics; multispectral signature control; and physical or biological effects on close observers.
Skywatcher: A privately funded, active ground-based UAP observatory project launched in 2024, using high-zoom EO cameras, SWIR and MWIR imagers, radar, and passive RF/SIGINT sensors with multi-sensor kinematic fusion.
SNR: Signal-to-Noise Ratio. The ratio of signal strength to background noise; determines whether a sensor can reliably detect a given target.
Spoofing: Intentional deception of a sensor by injecting counterfeit signals (e.g., false GPS positions, false radar returns producing "ghost" targets). One of the sensor failure modes enumerated in CU26.
Stewart Airport: Stewart International Airport / Stewart Air National Guard Base, New York; closed for approximately one hour on December 13–14, 2024 after drone activity, with one UAS reportedly approaching within 25–50 feet of a C-17.
SWIR: Short-Wave Infrared. The 1–3 μm spectral band; used to detect reflected sunlight signatures and discriminate material classes including those carried by certain balloons.

T

Tic Tac: The colloquial name for the unidentified object encountered by U.S. Navy F/A-18s of the USS *Nimitz* strike group in November 2004 off Southern California, given for its smooth pill-like shape; one of the most studied modern military UAP cases.
Transmedium: Movement across distinct physical domains (e.g., air to water, space to atmosphere) without apparent transition. One of the six observables.

U

UAP: Unidentified Anomalous Phenomena. Current U.S. government designation, replacing the earlier "Unidentified Aerial Phenomena" usage. Covers events that cannot be immediately identified across air, sea, space, and transmedium domains.
UAP Assessment Matrix (Lomas): Five-dimensional credibility-rating framework for UAP evidence proposed by Lomas, O'Malley, Masters, and Vernet (2025, \*Acta Astronautica\* 234: 491–503). Cited in CU26 as a more detailed scientific-credibility scale than the operational five-tier observer rating used in the Detect section.
UAP Independent Study: NASA-commissioned panel that issued its final report in September 2023, recommending (among other items) the expansion of ASRS to include systematic anomalous-event reporting by pilots and ATC.
UAPDA: UAP Disclosure Act. Proposed U.S. legislation establishing formal declassification processes, an independent review board with eminent-domain authority over recovered materials, and mandatory reporting requirements for federal agencies and contractors.
UAPTF: UAP Task Force. The 2020 predecessor of AARO, established under the Office of Naval Intelligence to standardize collection and reporting on UAP encounters.
UAS: Unmanned Aircraft System. An unmanned aircraft (commonly called a drone) together with its ground control station and communications equipment.
UAV: Unmanned Aerial Vehicle. A powered aircraft without an onboard pilot, controlled remotely or autonomously.
UFO: Unidentified Flying Object. Legacy term for anomalous aerial sightings, replaced in U.S. policy usage by UAP since 2022.
UnHidden: UK-based nonprofit producing training materials for healthcare providers on supporting patients reporting extraordinary experiences; cited as having no current U.S. equivalent.
Unified Command: An ICS structure in which multiple agencies with jurisdictional authority share command of an incident while preserving their statutory roles; CU26 notes its absence from the New Jersey drone response.
USAF: United States Air Force. Operated Project Blue Book (1952–1969) and currently operates NEXRAD radar stations jointly with NWS and FAA.
USAFE: United States Air Forces in Europe. The USAF major command headquartered at Ramstein; issued statements on the November 2024 incursions at RAF Lakenheath, Mildenhall, Feltwell, and Fairford.
USCG: United States Coast Guard. U.S. armed service operating under DHS in peacetime; provided observational reports of low-altitude aircraft near vessels during the December 2024 New Jersey drone wave.

V

Vandenberg SFB: Vandenberg Space Force Base, California; site of a November 30, 2024 incident in which a civilian (later identified as Chinese citizen and U.S. lawful permanent resident Yinpiao Zhou) was arrested for photographing the base by drone.
VASCO: Vanishing and Appearing Sources during a Century of Observations. Research project led by Beatriz Villarroel analyzing pre-Sputnik Palomar Observatory plates (1949–1957) for transient point sources; a 2025 *Scientific Reports* paper found transients clustered near nuclear-test dates and at rates consistent with sunlit objects in low Earth orbit.
VNIR: Visible and Near-Infrared. The 0.4–1.0 μm spectral band covering human-visible light and adjacent near-IR; the standard operating range of color cameras and most optical telescopes.
Volkel: Royal Netherlands Air Force base in the southeastern Netherlands; site where Dutch forces engaged drones with ground weapons in November 2025 without recovering the airframes.

W

Wright-Patterson AFB: U.S. Air Force base in Ohio; closed airspace for approximately four hours December 13–14, 2024 due to drone activity, with additional sightings on December 16–17.

Each entry is drawn from the working paper. Context and primary sources live there.

Read the working paper →