Abilities and Limitations of Eyewitnesses Assessed on Atmospheric Entries of Meteoroids and Artificial Satellites

Observers’ reactions to known phenomena with multiple witnesses provide a good test of their ability to accurately describe unfamiliar, brief, and unexpected events. We analyzed statistically about 300 accounts of 7 atmospheric entries of meteoroids and satellites reported to the French police during 1980-2009 and quantitatively estimated the reliability of witnesses for a dozen spatial, temporal, and structural characteristics. On a scale of 0 to 1, the reliability is practically zero for metric data and direction of motion, which cannot be determined in general from sensory data, and varies from 0.5 to almost 1 for directly perceptible characteristics. Witness reliability is not a simple concept as it is highly dependent on the characteristics being studied, the expected accuracy, and methodological constraints. It is also not a static notion because it can be improved by helping the witnesses provide objective information (e.g. angular data instead of metric data).