Great Comet of 1106

X/1106 C1, also known as the Great Comet of 1106, was a great comet that appeared on 2 February 1106, and was observed across the world from the beginning of February through to mid-March. It was recorded by astronomers in Wales, England, Japan, Korea, China and Europe. It was observed to split into many pieces, forming the Great Comet of 1843, Great Comet of 1882, Comet Pereyra, Comet Ikeya–Seki and C/2011 W3 (Lovejoy), as well as over 3000 small sungrazing comets observed by the SOHO space telescope. It is a member of the Kreutz Group, known as Subfragment I, a split from an earlier large (~150 km) comet that progressively fragmented under influence of the Sun.

A brief note in the Welsh manuscript known as the Brut y Tywysogion reads (in translation):

[-1106]. In that year there was seen a star wonderful to behold, throwing out behind it a beam of light of the thickness of a pillar in size and of exceeding brightness, foreboding what would come to pass in the future: for Henry, emperor of Rome, after mighty victories and a most pious life in Christ, went to his rest. And his son, after winning the seat of the empire of Rome, was made emperor.

The 1106 annal of the Peterborough Chronicle describes the comet. The Dorothy Whitlock translation reads:

In the first week of Lent, on the Friday, 16 February, in the evening, there appeared an unusual star, and for a long time after that it was seen shining a while every evening. This star appeared in the south-west; it seemed small and dark. The ray that shone from it, however, was very bright, and seemed to be like an immense beam shining north-east; and one evening it appeared as if this beam were forking into many rays toward the star from an opposite direction.

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