Phenomenon
Balloons
A lighter-than-air object — weather sonde, research payload, party or sky lantern — drifting with the wind rather than under power.
How it presents
- Track follows the prevailing wind at altitude, not a heading.
- No exhaust plume on infrared; thermal signature close to ambient.
- Apparent speed changes with the observer's own motion (parallax), not with the object's.
What this explanation does not settle
A balloon assessment explains the motion. It does not by itself identify the operator, the payload, or the launch point.
No published file in the archive currently carries this resolution. The page stays as a reference definition rather than being padded with unrelated material.