The 1566 Celestial Phenomenon over Basel (the Basel Broadsheet)

In 1566 news travelled on paper. Printed broadsheets were the sensational mass media of the day. That summer one came off the press in Basel. Its title promised "Seltzame gestalt", strange shapes seen in the sky three times that year, at Basel on the 27th and 28th of July and then on the 7th of August. The dates are Julian. The Gregorian calendar did not yet exist.

The text is credited to Samuel Coccius, who signed as "a student of the Holy Scripture and of the free arts, at Basel". The sheet was published by Samuel Apiarius, a printer who worked in Bern, Basel and Solothurn. Older English sources name Coccius alone.

27 July 1566. The sun had shone warm on clear, bright skies. Then, around 9 pm, "it suddenly took a different shape and color." It lost all its radiance and appeared "no bigger than the full moon." It seemed to weep tears of blood. All night the moon looked almost blood-red. At about six o'clock the next morning the sun rose "as if everything was blood-red and fiery".

Then came 7 August. At dawn, in the English rendering of C. G. Jung's 1958 book, "many large black globes were seen in the air, moving before the sun with great speed, and turning against each other as if fighting. Some of them became red and fiery and afterwards faded and went out."

The Swiss National Museum describes objects "shaped like cannonballs" that seemed to meet in battle formation. The sheet speaks of many who saw it. None is named.

The woodcut shows Basel's Münsterplatz, with the Basler Münster and a group of well-dressed spectators looking up. Above them hangs a sun with a stern human face, crowded by black and blank spheres. Beneath runs a long Christian warning. Those who live a pure Christian life have nothing to fear. Sinners will be judged. The print went into the collection of Johann Jakob Wick, a canon at the Grossmünster in Zurich. Today the Wickiana is held by the Zentralbibliothek Zürich. It is the only primary record. No inquiry followed, and no second account exists.

Most writers now read the sheet as natural sky phenomena seen through a religious lens. Robert Greenler pointed to halos, sun dogs and aurora. Swiss amateur astronomers found a questioned 1566 aurora entry in Hermann Fritz's 1873 catalogue of northern lights. The Swiss National Museum lists meteors, comets, Saharan dust and unusual atmospheric optics, and calls an extraterrestrial origin a minority view.

Jung saw natural events shaped by religious and military imagery. He suggested the spheres looked dark because the rising sun lit them from behind.

One popular claim does not hold up. Some summaries say a total lunar eclipse reddened the moon. NASA's catalogue lists only two eclipses in 1566, on 4 May and 28 October. Ulrich Magin argues the text follows an old stock motif, the sky battle as a warning from God. The Swiss daily 20 Minuten notes that broadsheets could exaggerate for effect. It still calls the cause unexplained.

Jung's book, published in English as Flying Saucers: A Modern Myth of Things Seen in the Skies, carried the sheet far beyond the German-speaking world. Ufologists came to read it as an aerial battle between unidentified flying objects. Jacques Vallée and Chris Aubeck included it in Wonders in the Sky in 2010. It is paired with its companion case, the 1561 celestial phenomenon over Nuremberg.