Trans-en-Provence

What GEPAN published

GEPAN, the Groupe d’Étude des Phénomènes Aérospatiaux Non-Identifiés (study group on unidentified aerospace phenomena) at the French space agency CNES, published the case as technical note no. 16, “Enquête 81/01, Analyse d’une trace” (investigation 81/01, analysis of a trace; CNES, Toulouse, 1 March 1983, 67 pages).

The note anonymises. The witness is “Monsieur COLINI”, a pseudonym; the village is “A1” and the locality whose gendarmerie came is “A2”; the private group whose investigator interviewed him is “XYZ”. The note never names Trans-en-Provence. The link comes from COMETA’s list of GEPAN’s notes, “N° 16, ‘Analyse d’une trace (cas de Trans-en-Provence)’” (no. 16, analysis of a trace, the Trans-en-Provence case; RG 255 413270, p. 83), and from a CNES brochure on SEPRA, which quotes the note under a summary of a case “dans la région de Trans en Provence” (in the area of Trans-en-Provence; PDF p. 8).

The note is published on GEIPAN’s website. On 15 and 16 October 2026 that address answered every request with 429 Too Many Requests. The link under “Sources” opens the Internet Archive’s copy of that same address, captured on 18 July 2024; it will be replaced by the official address when that answers. Page numbers below are those of the PDF.

Besides the witness’s statements, the note holds the gendarmerie’s description and photographs of the trace, where and when each sample was taken, the results of five soil laboratories and of the plant biochemistry, weather and air-traffic checks, and GEPAN’s synthesis.

The witness’s account

The gendarmerie took his statement on 9 January 1981 (p. 17):

“Hier, 8 Janvier 1981, comme pratiquement tous les jours j’étais en train de bricoler. […] Il était environ 17 heures. Le temps commençait à rafraîchir. Mon attention a été attirée par un léger bruit, une sorte de petit sifflement. Je me suis tourné et j’ai vu en l’air un engin qui se trouvait à la hauteur d’un gros pin en bordure du terrain.”

That is: yesterday, 8 January 1981, as on almost every day, I was doing odd jobs; it was about 5 pm and getting colder; my attention was caught by a slight noise, a kind of faint whistle; I turned and saw in the air a craft at the height of a big pine at the edge of the ground.

He saw it on the ground, “Aussitôt il s’est soulevé toujours en émettant un sifflement léger” (at once it rose, still giving a slight whistle), and left toward the north-east. “Je me trouvais à ce moment là à une trentaine de mètres du lieu d’atterrissage” (I was then about thirty metres from the landing place). The craft “avait la forme de deux assiettes renversées, l’une contre l’autre” (had the shape of two upturned plates, one against the other), about 1.50 m high, “la couleur du plomb” (the colour of lead) (pp. 17–18).

GEPAN heard him on 17 February 1981. With a single witness, it put the weight of that visit on the samples, and the reconstruction was done quickly: he was “extrêmement fatigué” (extremely tired; pp. 19, 25). Its estimates: the descent took “quelques secondes” (a few seconds), the craft stood on the ground for a few seconds, then “brutalement il s’élève à la verticale de quelques mètres” (abruptly it rises vertically a few metres) before leaving (pp. 20, 23); the whole sighting lasted “de l’ordre de 30 à 40 secondes” (on the order of 30 to 40 seconds), at a distance of between about 30 and 70 metres (p. 20). The versions of his account taken by the gendarmerie, by the investigator of “XYZ” and by GEPAN “diffèrent très peu sur le fond ; elles ne sont pourtant pas identiques, loin de là” (differ very little in substance, yet are far from identical; p. 27). He himself thought of a military craft: “c’est sans doute un engin militaire” (it is no doubt a military craft; p. 25).

GEPAN’s assessment of the witness (p. 66):

“L’enquête n’a pas mis en évidence, dans les discours successifs du témoin ni dans son comportement, d’indices qui pourraient être considérés comme révélateurs d’un processus particulier d’invention, d’exagération ou de déformation conduisant à mettre en doute son témoignage. Mais l’absence de preuve n’étant pas, là non plus, la preuve de l’absence, ceci ne suffit pas à certifier la véracité du témoignage.”

That is: the investigation found nothing in the witness’s successive accounts or his behaviour that would point to invention, exaggeration or distortion and so cast doubt on his testimony; but as absence of proof is not proof of absence, this does not suffice to certify that the testimony is true.

The trace and the samples

The gendarmerie, alerted by the witness’s neighbours, came on 9 January at about 11:30, noted the marks, heard the witness, “pris des photographies puis effectué des prélèvements” (took photographs, then samples; p. 5). Its description (p. 28):

“Nous constatons la présence de deux cercles concentriques l’un de 2,20 m de diamètre, l’autre de 2,40 m de diamètre. Les deux cercles laissent apparaître une couronne de 10 centimètres d’épaisseur. Sur cette couronne, sont nettement visibles deux parties diamétralement opposées de 0,80 m environ... et qui présentent des stries noires semblables à des traces de ripage...”

That is: two concentric circles, 2.20 and 2.40 m across, forming a ring 10 cm wide, with two diametrically opposite parts of about 0.80 m showing black streaks like skid marks. Four of the gendarmerie’s photographs of the trace are reproduced in the note (pp. 30–31).

GEPAN learned of the case on 12 January. Heavy rain had fallen over the weekend of 10–11 January, and GEPAN decided, after consulting the gendarmerie, not to go at once (pp. 5, 33). It went on 17 February, “soit 40 jours après l’observation” (that is, 40 days after the sighting), when the trace was still visible: “La terre y était fortement tassée, formant une croûte de l’ordre de un centimètre d’épaisseur” (the soil was strongly compacted, forming a crust about one centimetre thick; p. 28).

The samples (pp. 33, 42): soil from the ring taken by the gendarmerie on 9 January and a control taken by GEPAN on 17 February; wild alfalfa, Medicago minima, taken 1.5 m from the centre by the gendarmerie on 9 January, at 20 m as a control on 23 January, and at measured distances from the centre out to 10 m by GEPAN on 17 February. The note does not say whether any sample was kept after the analyses.

What the soil analyses found

The soil went to a CNES laboratory for microscopy and to four others: SNEAP at Boussens, the Université Paul Sabatier at Toulouse, the Université de Metz and the Laboratoire d’analyse physique at Pau (pp. 35–41). GEPAN gave the same questions to different laboratories so that their results could be checked against each other (p. 38). Their findings:

• CNES and SNEAP: striations and a compacted crust; iron, free or as oxide, plated on the limestone grains in streaks about a micron thick; and, by SNEAP, no organic compounds “caractéristiques de produit de combustion des moteurs utilisant des hydrocarbures” (characteristic of the combustion products of hydrocarbon engines; pp. 35, 38).
• Toulouse: a constituent in a single-crystal state that the control soil did not show (p. 38).
• Metz: black particles whose spectra “présentent des analogies avec ceux de certains polymères ou de résidus pétroliers” (resemble those of certain polymers or petroleum residues), and in conclusion “les particules noires macroscopiques semblent être des résidus de combustion” (the macroscopic black particles seem to be combustion residues; p. 39).
• Pau: “peu de différence significative entre le sol témoin et le sol sur lequel un dépôt est visible” (little significant difference between the control soil and the soil bearing the deposit); zinc and phosphate only, which the laboratory read as possibly coming “d’une peinture noire primaire à base de Carbon black” (from a black primer paint based on carbon black; p. 39).

GEPAN’s summary of the soil (p. 40): “une forte pression mécanique a été exercée (probablement due à un choc) en surface” (strong mechanical pressure was applied to the surface, probably from an impact), and “un échauffement thermique du sol, peut-être consécutif au choc, dont la valeur n’a pas excédé 600°” (heating of the soil, perhaps following the impact, which did not exceed 600°). And in its conclusion (p. 66): “Les interprétations possibles (choc, frottement...) restent cependant trop diverses et vagues pour que l’on puisse considérer qu’elles fournissent une confirmation définitive des narrations du témoin.” That is: the possible interpretations, impact or friction, remain too varied and vague to be taken as a definitive confirmation of the witness’s accounts.

What the plant analyses found

This part was done by Dr M. Bounias of the biochemistry laboratory of INRA, the national institute for agronomic research, at Avignon-Montfavet, who wrote sections 7.1 to 7.5 of the note himself (p. 42). In the first series, taken by the gendarmerie, leaves from 1.5 m showed a general weakening of pigments against leaves from 20 m (p. 45):

“Quel que soit l’âge des feuilles, les chlorophylles A sont abaissées de 33%, les chlorophylles B de 28% et la phéophytine de 31% […]. Parmi les caroténoïdes, le plus affecté est le β carotène qui est abaissé de 50 à 57% au voisinage du ‘phénomène’, ainsi que la violaxanthine (-80% chez les jeunes feuilles).”

That is: whatever the age of the leaves, chlorophyll A was down 33%, chlorophyll B 28% and pheophytin 31%; among the carotenoids the most affected was β-carotene, down 50 to 57% near the phenomenon, and violaxanthin, down 80% in young leaves.

The second series, which GEPAN took 40 days after the sighting from the centre of the trace outwards, showed changes that in most cases varied with the distance from the centre (pp. 50–60, 64). Comparing them with his own work on plants irradiated with gamma rays, Bounias wrote that nuclear radiation “ne présente donc pas d’analogie avec celle de la source énergétique impliquée dans le phénomène observé” (shows no analogy with the energy source involved in the observed phenomenon), and that a specific increase in the conversion of chlorophylls into pheophytins “pourrait être liée à l’action d’un champ énergétique de type électrique” (could be linked to the action of an electric-type energy field; pp. 64–65). He described further analyses as under way (p. 65).

GEPAN’s conclusion on the plants (p. 66): the knowledge of the damage plants can suffer remains “trop parcellaires pour que l’on puisse fournir dès à présent une interprétation précise et unique à ce remarquable faisceau de résultats” (too fragmentary to give, for now, a precise and single interpretation of this remarkable set of results); there is at least “une nouvelle confirmation d’un évènement de grande ampleur intervenu à cet endroit” (a further confirmation of a large-scale event at that spot). “Reste à savoir si cela correspond bien à la description fournie par le témoin.” That is: it remains to be seen whether this matches the description the witness gave.

What GEPAN concluded

GEPAN’s synthesis (p. 66): “Au plan pédologique les conditions particulières du terrain ne permettaient guère une appréciation quantitative précise de masse, de pression, d’échauffement.” That is: on the soil, the particular conditions of the terrain hardly allowed a precise quantitative estimate of mass, pressure or heating. It could show qualitatively a large-scale event with mechanical deformation, heating and perhaps some trace deposits, but not tie it to the witness’s account. Its last sentence (p. 67): the investigation “pose plus de questions qu’elle n’apporte de réponse mais cette fois-ci les questions semblent être bien posées et, à ce titre, cette enquête du GEPAN est plus enrichissante que toutes celles faites jusqu’à présent” (raises more questions than it answers, but this time the questions seem well put, and in that respect this GEPAN investigation is more rewarding than all those made so far).

Later texts went further than the note:

• The CNES brochure on SEPRA (PDF p. 8) has the phenomenon resting on the ground: “il aurait stationné plus d’une minute” (it is said to have stayed more than a minute). The note puts the whole sighting at about 30 to 40 seconds.
• The same page: “Les résultats éliminent l’hypothèse d’un phénomène atmosphérique rare ou la présence d’aéronefs civils et militaires.” (the results rule out a rare atmospheric phenomenon or the presence of civil and military aircraft). The note records an Alouette II helicopter flying over the area “à une hauteur de 200 m du sol aux environs de 16h.30 locales” (at 200 m above the ground at about 4:30 pm local time; p. 34) and does not rule it out.
• The brochure says the plant analyses show “une modification profonde des métabolites vraisemblablement causée par un champ électromagnétique intense” (a profound change in the metabolites, probably caused by an intense electromagnetic field), and quotes, just below, the note’s sentence that knowledge of plant damage is too fragmentary for a precise and single interpretation.
• COMETA, in 1999, wrote that the analyses “showed unequivocally that it really was a case of an unidentified heavy metal object that had actually landed on the platform of earth” (RG 255 413270, p. 26). The note says that the interpretations are too varied and vague to confirm the witness’s account.

GEIPAN’s current classification of the case could not be checked: its server refused requests (429).

Where it was

The note places the property 2 km east of the village “A1”, which lies 3 km south of the locality “A2”, on the side of a hill above a valley (p. 6). The CNES brochure puts the case “dans la région de Trans en Provence” (in the area of Trans-en-Provence). The pin is OpenStreetMap’s point for the commune of Trans-en-Provence (relation 190815), rounded by us to 43.50° N, 6.49° E; it marks the commune, not the property.

Why this scores where it does

Witnesses: 2. One witness. GEPAN found no sign of invention or exaggeration, and said that this does not certify his account.

Radar: 0. None.

Optics: 1. Photographs of the trace by the gendarmerie and by GEPAN; none of the object.

Physical trace: 4. A trace described, photographed and sampled by the gendarmerie the morning after, and analysed by five soil laboratories and a plant biochemist. Not 5: GEPAN wrote that the terrain hardly allowed a precise estimate of mass, pressure or heating, and the full series of plant samples was taken 40 days later, after heavy rain.

Multi-channel: 2. The witness’s account and the trace he showed; nothing else recorded the craft.

Documentation: 5. A 67-page technical note with the gendarmerie’s statement and photographs, the provenance of every sample, each laboratory’s results and GEPAN’s synthesis.

Anomaly: 3. A trace and plant changes that GEPAN could not attribute to any known cause, but whose interpretations it called too varied and vague to confirm the account.

Data today: 3. The note can be read, for now only through an archive copy, and it does not say whether the samples were kept.

The overall is 2.5: class C, material gaps.

What would settle it

• The samples, if they were kept, analysed again; the note does not say whether they were.
• The gendarmerie’s own file: the full statement, the report and the photographs, of which the note reproduces extracts.
• The further plant analyses Bounias described as under way in March 1983, and any report on them.
• A comparison of the trace with marks left on the same kind of ground by a known heavy object or vehicle, which the note does not make.