Consideratio & observatio cometae aetherei astronomica qui anno MDLXXX mensibus octobri, novembri et decembri in alto aethere apparvit

The redness is frequently changed into yellow, white, saffron, blue, and black. There was no spectator without horror. And so that nothing of the magnitude of the miracle would be missing: The whole sky seemed to blaze with flames, ignited globes, and bloody spicula; only the meridional region, which is enclosed by the circle from the African the South-West through the section of the Meridian and Tropic, up to the Meseurum a reference to the West-North-West point, remained blue, and felt nothing of this portent. However, between the zenith and the section of this circle with the Meridian, a certain small area or abyss of saffron color is seen, toward which all the spicula, weapons, and spears in general converge from all around, as if toward a target, and soon retreat, and having restored their rank, they contend toward the same place with a great rush, yet nevertheless, that abyss remains in the middle, until they finally all disappeared, which, however, were observed by the night watchmen to return from the East for the most part after the 3rd hour of the night. But all these things were carried out with such brightness that I would have thought that night was illuminated by the moon shining with a full orb.

More horrible was the confusion, vibration, movement, and fighting of the clouds and ignited spicula, which appeared with a dire aspect on the 21st of September. Two armies meeting each other, from the East and the West, were seen fighting with great force; when the former emerged from the East, with great brightness, and that not unpleasant (unless, as it was rising at an unusual time, it could indicate that something else was to follow), it illuminated the lands, no differently than if the Moon were just about to ascend above the horizon and spread its rays. It was extended, however, into the North, upon which it soon changed its white or saffron color into bloody. In the same way, the other, arriving from the West, meets it from the opposite direction. They occupied, therefore, half the sky between the zenith and the horizon.