James Oberg often writes about alleged UFO sightings, giving scientific explanations to seemingly extraterrestrial phenomena, or otherwise debunking them as hoaxes.
Oberg categorized UFO sightings (excluding those identified as hoaxes) into one of three groups:
- Super-High Plumes – rocket or missile plumes, especially lit by the sun on a dark sky;
- Space “Dandruff” – ice flakes, fragments of insulation, etc. flying alongside a space vehicle, especially seen by backward-facing cameras;
- Twilight Shadowing – objects that move from shadow into sunlight in space appear as if coming from behind the clouds or from beyond the edge of the Earth.