Bonilla's objects crossing the solar disc

Witness account

Bonilla reported numerous small bodies crossing the projected solar disc on 12 and 13 August 1883 and described photographs taken through his telescope. His published count for the first day is 283 plus 48, or 331; the next day's account gives a further 116. He said the objects appeared dark against the Sun and luminous when outside its disc.

Public record

The original French report and its illustration are accessible in the 1885 volume of L'Astronomie. Bonilla explicitly states that the object was in focus while the Sun was not. The journal's editorial note suggests birds, insects, or other atmospheric particles. A 2011 research preprint later proposed a fragmented comet, a conditional reconstruction rather than a newly detected historical object.

Sources

• José A. y Bonilla, Passage sur le disque solaire d'un essaim de corpuscules, L'Astronomie 4 (September 1885), 347–350; full-volume scan and OCR
• H. Manterola et al., Interpretation of the observations made in 1883 in Zacatecas (Mexico): A fragmented comet that nearly hits the Earth, 2011 preprint