During the Middle Ages, the appearances of Comet Halley marked the passage of time: It was in the sky in the years 530, 607, 684, 760, 837, 912, 989, 1066, 1145, 1222, 1301, 1378 and 1456. Many of its apparitions were very bright and were well-observed in Europe and Asia.

The return in the late summer of 530 was preceded, on 9 April of the same year, by a great meteor shower, when the Earth passed through the orbit. This produced a major outburst of the Eta Aquarid meteor shower, which may be observed every year in April and May. In the Nuremberg Chronicles, the appearance of Comet Halley in 684 was held to be responsible for ‘great rains and lightning strokes’ with injuries and deaths in Italy and Rome. In China the comet was seen for 33 days. Korean and Japanese observations have also been preserved with those from China.

At Easter in 837, Comet Halley made its closest approach to Earth in recorded times. It was less than 5 million kilometres from the Earth. That corresponds to about 13 times the distance to the Moon. At this return the tail was well over 120° long, and the comet's overall magnitude was −4 mag. It was observed from March to May, during which time the tail pointed in every direction in succession on the sky. According to legend, Louis the Pious took the comet as a sign for a return to God, although his chronicler Aginard said to him “Do not fear signs in the heavens, they only frighten fools.” Just one year later, in November and December, another ‘dreadful’ comet appeared, which ‘stretched across the whole sky’.

In 905, a very bright comet appeared in the daytime sky from 18 May. Chroniclers reported ‘a terrible, large, and impressive comet, which terrified everyone that saw it’. In May and June, after perihelion, it was in the evening sky, and its tail reached 100° in length.

Just as in art, for a long time the comet motif in literature was bound up with negative astrological meaning. Only with the Enlightenment did it become possible to employ comets in a metaphorical sense in other contexts. Since the second half of the nineteenth century, comets have been a central motif in science fiction.

Early modern times

“When beggars die there are no comets seen / the heavens themselves blaze forth the death of princes.” This famous verse from the second act of Shakespeare's tragedy ‘Julius Caesar’ dates from 1599. Shakespeare compressed the entire literary role of comets into one sentence, which he put into the mouth of Calpurnia, Caesar's wife. The statement is quite in accord with the ancient astrological interpretation.

Until well into the eighteenth century, it was no different in German-speaking countries. Among many similar tales, the ‘Kometspiegel’ (‘Comet mirror’) of Thomas Hartmann, written in Halle in 1606, has become famous, and which, in a mixture of Christian fear of comets and astrological interpretation, lists the threats to mankind posed by a comet:

“All comets indeed give evidence / of a lot of bad luck, affliction, peril and danger / and a comet never appears / to be cares without evil meaning / in general eight kinds of affliction occur / when a comet burns in the air:

1. Much fever, illness, pestilence and death,

2. Difficult times, shortages and famine,

3. Great heat, droughts and infertility,

4. War, rapine, fires, murder, riots, envy, hatred and strife,

5. Frost, cold, storms, weather and lack of water,

6. Great increase in people going into decline and death,

7. Conflagrations and earthquakes in many places,

8. Great changes in government.

But for us to do penance from the heart, God afflicts us with disasters and pains.”

The Enlightenment and Romanticism

About the middle of the eighteenth century, in parallel with the scientific revelations about comets, the literary point of view also changed. Authors during the Enlightenment discovered comets as an ideal motif.