José Bonilla UFO Observation

On the morning of August 12, 1883, in the high desert of central Mexico, an astronomer sat at his telescope doing routine work. Jose Arturo y Bonilla was the director of the Zacatecas Observatory, a small but respected institution perched at an altitude of nearly 2,500 meters in the mountains of Zacatecas state. His task that day was unremarkable — he was conducting solar observations, using a telescope fitted with a camera to record the sun’s surface as part of an ongoing scientific study. The sky was clear, the equipment was functioning properly, and nothing about the morning suggested that it would produce anything other than the usual data. Then something crossed the face of the sun.

Not one something. Hundreds of somethings. Over the course of two days, Bonilla observed and photographed approximately 447 objects passing across the solar disc — dark shapes, surrounded by luminous mist, moving in formations that matched no known celestial phenomenon. His photographs, captured on wet plate negatives, may represent the first photographic images of unidentified flying objects in human history. They were published in a French scientific journal three years later, accompanied by an editor’s note suggesting they were merely birds or insects. Bonilla disagreed. The debate that followed has never been fully resolved, and his observations remain one of the most intriguing and contested episodes in the prehistory of the UFO phenomenon.

The Observer and His Observatory

Jose Arturo y Bonilla was not a crank, an amateur, or a sensation seeker. He was a trained astronomer serving as the director of a recognized scientific institution. The Zacatecas Observatory, while modest in comparison to the great observatories of Europe and North America, was a legitimate scientific facility conducting real research. Its location in the high desert of central Mexico provided excellent observing conditions — clear skies, low humidity, and minimal light pollution — that made it well suited for solar and stellar observation.

Bonilla had spent years conducting systematic observations of the sun, recording sunspot activity, solar prominences, and other phenomena as part of the international effort to understand solar behavior. His work required patience, precision, and a thorough familiarity with the appearance of the sun through a telescope. He knew what the sun looked like. He knew what sunspots looked like. He knew what birds, insects, and atmospheric debris looked like when they crossed his field of view. And he knew, immediately, that what he was seeing on August 12, 1883, was none of these things.

The telescope Bonilla used was equipped for solar observation, fitted with filters to reduce the sun’s brightness to a level safe for viewing and photography. The camera attached to the telescope used wet plate negatives — glass plates coated with light-sensitive collodion that had to be prepared, exposed, and developed within a short window of time. The process was cumbersome but produced high-quality images with excellent resolution. The photographs Bonilla captured that day were technically competent, clearly showing the objects silhouetted against the bright disc of the sun.

The Observation

Bonilla’s observation began on the morning of August 12, 1883, and continued into August 13. Over this two-day period, he counted a total of 447 objects crossing the face of the sun. The objects appeared singly and in groups, some traveling in apparent formation, others moving independently. They crossed the solar disc at various angles and speeds, some traversing the entire disc while others appeared to cross only a portion before moving out of the field of view.

Bonilla described the objects as dark, irregularly shaped bodies of varying sizes. Some appeared roughly circular; others were elongated or angular. Their edges were not sharply defined — instead, each object appeared to be surrounded by a luminous haze or mist that gave it a slightly fuzzy appearance against the bright background of the sun. This mist or atmosphere was one of the features that most puzzled Bonilla, as it was inconsistent with the appearance of any known object that might cross the solar disc.

The objects were not stationary. They moved across the face of the sun at speeds that varied from object to object and sometimes varied for individual objects during their transit. Some moved in straight lines; others followed curved or irregular paths. Some appeared to change speed during their transit, accelerating or decelerating in ways that suggested motive power rather than passive drift. In several instances, objects appeared to move in coordinated groups, maintaining consistent spacing and direction as if flying in formation.

Bonilla estimated that the objects were at a considerable distance from the observatory — far enough to be silhouetted against the sun but close enough to show discernible shape and structure through his telescope. This estimate would become a crucial point of contention in subsequent debates about the nature of the objects. If they were close to the telescope — insects on a nearby surface, birds in the middle distance — they would not have been visible against the sun in the manner Bonilla described. If they were distant — in the upper atmosphere or beyond — their size and nature became far more difficult to explain.

On the first day, August 12, Bonilla counted 283 objects. On the second day, he counted 164. The observation ended when clouds moved in and obscured the sun, preventing further observation. Whether additional objects would have been counted under clear conditions is unknown.

The Photographs

Bonilla’s photographs are the most significant aspect of his observation. In an era when UFO reports relied entirely on verbal testimony, Bonilla provided physical evidence — images captured through a scientific instrument by a trained observer using established photographic techniques.

The wet plate negatives show the solar disc with small dark shapes visible against the bright surface. The shapes are clearly distinct from sunspots, which have characteristic appearances — dark umbrae surrounded by lighter penumbrae — that are familiar to any solar observer. The objects in Bonilla’s photographs lack the structure of sunspots and are positioned at various points on the solar disc, some near the limb (edge), others near the center.

The photographs also show the luminous mist or haze surrounding some of the objects, visible as a lighter zone around the dark central shape. This detail is important because it would be difficult to produce artificially on a wet plate negative — the haze has a natural, graduated quality that suggests it was genuinely present in the optical image rather than being an artifact of the photographic process.

The number of photographs Bonilla produced is not precisely documented in all sources, but he captured multiple images over the two-day observation period. The fact that the objects appear at different positions on the solar disc in different photographs is consistent with objects in motion, ruling out static artifacts on the telescope optics or the photographic plates themselves.

These photographs may represent the first photographic evidence of unidentified aerial phenomena. Earlier UFO reports — the Rhine Valley sightings of the medieval period, the “celestial battle” over Nuremberg in 1561, the Basel phenomenon of 1566 — were recorded only as written accounts and woodcut illustrations. Bonilla’s images, captured through a telescope with a camera, represent a quantum leap in the documentation of aerial anomalies.

Publication and Reception

Bonilla submitted a report of his observations to L’Astronomie, the French astronomical journal founded by Camille Flammarion. The report was published in 1886, three years after the observation — a delay that was not unusual in scientific publishing of the period but that meant the observations had little immediate impact.

The editor of L’Astronomie appended a note to Bonilla’s report suggesting that the objects were most likely birds, insects, or other small creatures passing between the telescope and the sun. This editorial commentary shaped the reception of the report, providing skeptics with a ready-made explanation and framing the observation as a curiosity rather than a discovery.

Bonilla himself disputed the editor’s interpretation. He pointed out several features of his observation that were inconsistent with the bird or insect hypothesis. The objects appeared to be at a great distance from the telescope, far beyond the range at which individual birds or insects would be visible as defined shapes. The luminous mist surrounding the objects was not a feature of any known bird or insect. The number of objects — 447 over two days — was far greater than any normal flock of birds, and the pattern of their movement was inconsistent with the behavior of migrating or feeding birds. The extended duration of the observation — hours spread across two days — was difficult to reconcile with the transit of insects or birds across a telescope’s narrow field of view.

Despite Bonilla’s objections, the editorial note’s suggested explanation became the default interpretation among those who encountered the report. The observation was filed away as a minor curiosity in the annals of astronomy, mentioned occasionally in discussions of unusual celestial phenomena but not taken seriously as evidence of anything extraordinary.

Modern Reanalysis

The Bonilla observation attracted renewed attention in the late twentieth and early twenty-first centuries as researchers in both UFO studies and astronomy revisited historical records for evidence of anomalous aerial phenomena.

In 2011, a team of researchers at the National Autonomous University of Mexico published a paper proposing a new interpretation of Bonilla’s observation. They suggested that the objects he photographed were fragments of a comet that had broken apart and was passing close to the Earth. According to their calculations, a comet nucleus fragmenting at a distance of a few thousand kilometers from Earth would produce exactly the kind of visual appearance Bonilla described — dark bodies surrounded by luminous mist (outgassing material), moving across the field of view at varying speeds and angles.

This hypothesis was provocative because it implied that in August 1883, the Earth had a close encounter with the debris field of a fragmenting comet — an event that, had any of the fragments entered the atmosphere, could have caused significant destruction. The researchers estimated that the fragments ranged in size from approximately fifty to several hundred meters in diameter, and that the total mass of the debris field was comparable to the object that struck Tunguska, Siberia, in 1908.

The comet fragment hypothesis explains several features of Bonilla’s observation that the bird/insect hypothesis does not. The luminous mist is consistent with cometary outgassing. The irregular shapes are consistent with fragmented rocky or icy bodies. The large number of objects is consistent with a comet breaking apart into hundreds of pieces. And the fact that the objects were visible only from Zacatecas and not from observatories in other locations is consistent with a parallax effect — objects close to Earth would appear in different positions against the sun when viewed from different latitudes, and might not cross the solar disc at all from some observation points.

However, the hypothesis has been challenged on several grounds. No other observatory reported unusual objects crossing the sun on August 12-13, 1883, even at locations where the comet fragments should have been visible if they were at the distances proposed. No historical records indicate meteor showers or atmospheric events consistent with cometary debris passing close to Earth on those dates. And the behavior of some of the objects — changing speed, moving in apparent formation — is not consistent with passively drifting comet fragments.

The UFO Interpretation

For researchers interested in the history of UFO phenomena, the Bonilla observation holds a special place. It predates the modern UFO era by more than six decades, demonstrating that anomalous aerial objects were being observed and documented by trained scientists long before the term “flying saucer” entered the popular lexicon.

The objects Bonilla photographed exhibited characteristics that would become familiar in later UFO reports — dark shapes against the sky, luminous auras, movement in formation, and behavior that suggested controlled flight rather than natural drift. The observation was made by a credible witness using scientific equipment, and it was documented with photographs and published in a scientific journal. By the standards of UFO evidence, the Bonilla observation is exceptionally well documented for its era.

The case also illustrates the challenges that have always attended UFO reports from credible observers. Bonilla’s observation was effectively dismissed by the scientific establishment through the simple expedient of an editorial note suggesting a mundane explanation. The social dynamics of credibility — the reluctance of scientists to endorse anomalous claims, the tendency of institutions to default to conventional explanations, the pressure on observers to accept skeptical interpretations of their own experiences — were already in operation in 1883, decades before the UFO controversy generated the fierce institutional resistance that characterizes the modern era.

What Bonilla Saw

More than 140 years after Jose Bonilla sat at his telescope and watched 447 objects cross the face of the sun, the nature of those objects remains uncertain. They may have been birds or insects, as the editor of L’Astronomie suggested, though Bonilla’s own arguments against this interpretation are compelling. They may have been fragments of a disintegrating comet, as the 2011 analysis proposed, though the absence of corroborating observations is troubling. They may have been something else entirely — something that the scientific knowledge of 1883, and perhaps the scientific knowledge of our own era, is not equipped to identify.

What is certain is that Bonilla observed something real. The photographs exist. The objects were there, crossing the sun, numbered and counted and recorded by a man whose professional competence and intellectual honesty are not in question. The objects moved. They had shape and structure. They were surrounded by something that glowed. And then they were gone, passing out of the telescope’s field of view and into the vast uncertainty that separates observation from explanation.

The Bonilla photographs sit in the archive, more than a century old, their wet plate negatives preserving an image of something that has never been conclusively identified. They are the earliest photographic record of anomalous aerial objects — a distinction that may seem minor in an age saturated with images of everything from surveillance footage to satellite photography, but that in 1883 represented something unprecedented: a moment when the technology of observation captured something that the framework of understanding could not accommodate.

Jose Bonilla pointed his telescope at the sun and saw what he saw. He photographed it. He reported it. He stood by his observation when it was dismissed. The objects crossed the solar disc and vanished, leaving behind only the images on the glass plates and the questions that no one has yet been able to answer. In the bright disc of the sun, for two days in August 1883, something moved that science has not explained — and the first photographs of the unexplained were taken by a man who was simply doing his job, looking at the sun, and paying attention to what he found.

Sources

• Bonilla observation — Wikipedia
• World Digital Library — Latin America — Latin American primary sources