The Great Comet of 1858: A Road Sign to the Stars

During an expedition to the Texas-Mexican border area in September-October 1858, the Belgian astronomer Jean-Charles Houzeau (1820-1888) admired "a beautiful comet" . At that moment, he was not aware that the comet had already been discovered in June 1858 by Giovanni Battista Donati. Houzeau sent detailed descriptions of his whereabouts to his family and to a colleague at the University of Brussels. Donati's comet, with its curved tail extending 40 degrees across the sky, became a big news event, and inspired visual artists worldwide. Many paintings and sketches were produced. Some of these artworks show quite literal transcriptions of the surroundings, and even have scientific overtones, whereas others are more artistic than exact. The comet also inspired jewelry artisans, and poets: some lyric poems include just like some artworks do - elements that refer to mid-nineteenth century scientific developments. A basic ephemeris analysis shows that the cometary passages allegedly attributed to the same comet in the time span 104-1858 AD cannot be assigned to a single comet. An analysis of a drawing by William Hayes Hilton leads to the conclusion that the artist could not possibly have painted the landscape and the starscape at the same moment and at the date suggested by the position of the comet with respect to the star Arcturus. A similar conclusion is reached for a painting by British artist William Dyce. The artistic representations of this comet indirectly contributed to familiarization of the mid-nineteenth century public with some specific stars and constellations. As such, Donati's comet showed the road to the stars.