AARO_Puerto_Rico_UAP_Case_Resolution.pdf

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All-domain Anomaly Resolution Office (AARO) 
U.S. Department of Defense 
Case: “The Puerto Rico Object” 
Case Resolution | 20 March 2025 
Case Synopsis 
Location:  Puerto Rico 
Date:  April 26, 2013 
Object Altitude (Reported): N/A 
Object Altitude (Assessed): 656 ft 
Object Speed (Reported): N/A 
Object Speed (Assessed): 8 mph 
Object Shape (Reported): N/A 
Object Shape (Assessed): Indistinct 
Reporter: Publicly available media, originally 
recorded by U.S. Customs and Border 
Protection. 
Data Type: Infrared 
Reported Behavior: Split or replicated; 
transmedium…

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video’s diminishing quality over time. Figure 1 reconstructs the aircraft's flight path, sensor line-
of-sight to the ground, and position relative to the objects. 
Figure 1: A reconstruction of the CBP aircraft's flight path is shown in green. Grey lines 
indicate the sensor's line-of-sight to the ground from the aircraft. The yellow arrow shows the 
objects’ assessed flight path. 
Key Findings  
AARO assesses with high confidence that: 
•
The objects did not exhibit anomalous speeds or other behavior exceeding known state-
of-the-art performance characteristics…

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Performance Characteristics 
Object Speed: Systems Toolkit (STK) reconstruction determined the objects drifted at 
approximately 3.6 meters per second (8 mph) in a straight line over land, consistent with the 
recorded wind speed of 4.4 meters per second (9.8 mph) from the east/northeast.2 
The objects’ apparent high speed is attributable to motion parallax. Motion parallax is an optical 
effect that induces an observer to perceive that a stationary or slow-moving object is moving 
much faster than its actual speed when viewed from a moving frame of reference. Th…

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Figure 2: Stills images of object separation from within the first minute of the video. 
Figure 3: These stills demonstrate how the changing view angle from the sensor to the objects 
influenced their perceived behavior as the aircraft gained altitude. They appear to be one object 
from a low angle and a low magnification, as shown in Image A at 00:05.14. The objects appear 
distinct from one another from a steeper viewing angle and moderate magnification, as shown in 
Image B at 00:33.41. Image C, at 02:37.44, shows the objects from a high angle and increased 
m…

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Observable Characteristics and Attribution 
Size and Shape: AARO employed pixel analysis to estimate the objects’ sizes to be smaller than 
one meter (three feet).  Pixel analysis is a method of measuring an object’s size by comparing it 
to an object of known dimensions.  The objects’ shapes are indistinct. 
Number of Objects: AARO assesses with high confidence that the video footage depicts two 
objects traveling near each other rather than a single object splitting into two. 
Attribution: AARO assesses with moderate confidence that the objects depicted in the …

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Data Quality and Methodology 
AARO assesses that the sensor data associated with the encounter provides sufficiently detailed 
information to resolve this case with high confidence. AARO’s assessment is informed by 
reconstruction of the event using STK and Minimum Separation Vectors analysis. 
Sensor Effects and Limitations 
Thermal imaging can fail to differentiate a target object from the background when its thermal 
signature is virtually identical to the surrounding environment to be distinct, known as thermal 
crossover. When a sensor fails to discriminate …

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makes identification difficult. AARO considered this interpretation unlikely, as the STK 
reconstruction demonstrates that the objects moved in a straight line at wind speed over land. 
Further, birds viewed through an IR sensor at the distances involved in this encounter would 
retain identifiable features, such as wings, or pulsate at the frequency of wing beats. 
Mylar Balloons: An AARO partner assessed that the objects were a pair of mylar or “party” 
balloons. The objects’ behavior is consistent with a pair of balloons drifting together and apart 
while tied…