Phenomenon
Birds and other wildlife
Biological targets — single birds or flocks — resolved by an imaging sensor at a distance that removes scale cues.
How it presents
- Warm against a cold sky on infrared, with a flicker at wingbeat frequency.
- Erratic short-radius turns that no airframe could survive if the object were large.
- Object size collapses once true range is established.
What this explanation does not settle
Wildlife explains shape and motion. It does not explain radar returns from an object with no biological cross-section.
No published file in the archive currently carries this resolution. The page stays as a reference definition rather than being padded with unrelated material.