Do the object's reported course, size and motion fit a small balloon drifting on that evening's wind?
Where it stands
Two answers have been proposed. None is ahead on the evidence yet. Two are still possible.
Why it matters
A balloon was the witnesses' own first thought, and the weather and the geometry can test it.
Answers 2
The tests
| Measurement · 95% intervaldegrees | within witness course error and wind turning with heightpredicts −60 to +60 | well across the wind (westward side)predicts −180 to −60 | Weighs |
|---|---|---|---|
| Reported course minus downwind direction, 3 Aug 1947 eveningno interval given | — | — | — |
| Find the evening pilot-balloon winds for Newark or LaGuardia, 4 Aug 1947 00Znot measured yet · a next step | Planned | Planned | — |
| The measurement doesn’t separate the answers. Each cell is computed from the interval and the answer’s predicted range; a measurement that fits every answer weighs nothing. | |||
Next steps 3
Details
Look for 1947 upper-air (pibal) winds in NOAA IGRA or the Weather Bureau's printed winds-aloft records. Wind near 200-300 m from the south or south-south-west would close the 41-degree gap and support a balloon; wind from west or north-west would rule out free drift.
Details
Wind near 200-300 m from the south or south-south-west closes the gap; from west or north-west it rules out free drift.
Details
Find Newark or LaGuardia pilot-balloon winds near 200-300 m for the evening of 3 August 1947; south or south-south-west closes the course gap, west or north-west rules out free drift.
History
- Federal Bureau of Investigation, Newark Division: the reported course is 41 degrees left of downwind, and a small near balloon matches the reported size and speedFor: Yes: within the error of a course rebuilt from landmarks days later
- NOAA National Centers for Environmental Information: the reported course is 41 degrees left of downwind, and a small near balloon matches the reported size and speedFor: Yes: within the error of a course rebuilt from landmarks days later
- Session 1: raised the question, ran one test and found one result bearing on its answers