UAP Sensor Types — FLIR, Electro-Optical, and Radar
Modern military UAP observations are captured by three primary sensor classes — forward-looking infrared (FLIR), electro-optical (EO), and radar — each with distinct strengths, characteristic artifacts, and analytical limitations that shape how PURSUE-catalog videos read on screen.
Modern military UAP observations are captured by three primary sensor classes: forward-looking infrared (FLIR), electro-optical (EO), and radar. Each class has distinct strengths and characteristic artifacts that shape how AARO assesses the underlying observation and how the resulting video reads to a viewer. The Pentagon's PURSUE catalog contains examples of all three: FLIR captures dominate the modern CENTCOM, INDOPACOM, and NORTHCOM video set (including the 2017 Navy GOFAST clip and the 2023 F-16 Lake Huron engagement); EO captures appear in NASA's Apollo lunar-surface photographs and a 2023 ellipsoid-bronze-metallic-object FBI photograph; radar tracks appear as supporting evidence for the 2004 USS Nimitz Tic Tac encounter (the USS Princeton's AN/SPY-1 radar). Understanding which sensor produced an image is critical to assessing what its apparent behavior actually means.
“The object is not actually close to the water, but is rather closer to 13,000 feet.”
Forward-looking infrared (FLIR)
FLIR is a passive thermal-imaging sensor that detects mid-wave or long-wave infrared radiation. FLIR works at night, sees through smoke and light cloud, and captures heat signatures invisible to the visible-light cameras. FLIR is the most-common modern UAP sensor in the PURSUE catalog because the U.S. military's tactical aircraft (F/A-18 ATFLIR, F-16 Sniper-XR, F-35 EOTS) all carry FLIR-equipped targeting pods. FLIR's analytical limitation: 'black-hot' versus 'white-hot' polarity inversions, parallax artifacts at long sensor range, and pod-gimbal-lock artifacts can all mimic anomalous behavior that the underlying object does not actually exhibit.
Electro-optical (EO) and visible-light
Electro-optical sensors capture visible-light imagery in the conventional photographic sense. EO appears in the PURSUE catalog primarily as NASA's Apollo 12 and Apollo 17 lunar-surface photographs, FBI black-hot infrared captures from September and December 2025, and a 2023 ellipsoid-bronze-metallic-object photograph from a southeastern U.S. encounter. EO captures preserve color and surface detail that FLIR loses but require daylight and reasonably-clear atmospheric conditions. EO's analytical advantage over FLIR is that color, material reflectivity, and shadow geometry constrain the identification more tightly.
Radar (AN/SPY-1, AN/SPY-6, AN/APG-79)
Radar provides ranged tracking data — position, velocity, altitude — independent of visible-light or thermal-imaging conditions. The most-cited radar contributions to the modern UAP record come from the U.S. Navy's AN/SPY-1 (Aegis Combat System cruiser/destroyer radar, used aboard the USS Princeton during the 2004 Tic Tac encounter), the more recent AN/SPY-6 (Flight III Aegis), and the F/A-18E/F's AN/APG-79 AESA fire-control radar. Radar tracks corroborate visual or FLIR observations and provide kinematic ground truth — track velocity, acceleration, and altitude — that pure visual reports cannot establish. Radar tracks also have characteristic clutter and electronic-warfare artifacts that must be ruled out.
Multi-sensor corroboration in AARO assessments
AARO's status code 'corroborated' typically requires multi-sensor evidence — for example, a FLIR clip backed by an independent radar track. AARO's status code 'resolved' typically requires either multi-sensor corroboration of an identified platform (the February 2023 Chinese balloon: U.S. F-22 visual, AN/APG-77 radar, ground-based weather radar, and post-recovery debris analysis) or a single-sensor analysis that definitively explains the apparent anomaly (the 2017 GOFAST: pure ATFLIR analysis combined with geospatial trigonometry).