What happened
On January 8, 1981, at about 5 p.m., Renato Nicolaï, a retiree from Trans-en-Provence, was working in his garden when he heard a soft whistling sound. He saw an object shaped like two plates placed rim to rim, about 2.5 meters in diameter, which landed on a terrace of his property and, after several tens of seconds, rose and flew away. A circular mark of compacted, blackened soil was left at the landing site. The gendarmerie took samples of soil and plants, and the case was taken up by GEPAN, an agency attached to the French space research center CNES. Studies led by Jean-Jacques Velasco, with the participation of biologist Michel Bounias, found changes in the soil and in the chlorophyll content of alfalfa leaves that depended on the distance from the center of the mark.
Witnesses
Renato Nicolaï, the only witness.
Explanations and hypotheses
GEPAN concluded that the traces indicated strong mechanical pressure and heating, and it could not explain the changes in the plants. Skeptics, including Eric Maillot, questioned the research methodology and suggested that the mark could have been left by an ordinary vehicle or construction machine. The case is one of the most frequently cited pieces of physical evidence in the history of ufology, but it remains unresolved.
Unexplained There is no convincing explanation.
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