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arXiv · 2206.10827

The Great Comet of 1106, a Chinese Comet of 1138, and Daylight Comets in late 363 As Key Objects in Computer Simulated History of Kreutz Sungrazer System

Zdenek Sekanina·Rainer Kracht
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Abstract

We present the results of our orbital computations in support of the recently proposed contact-binary model for the Kreutz sungrazer system (Sekanina 2021, 2022). We demonstrate that comet Ikeya-Seki (C/1965 S1) previously passed perihelion decades after the Great Comet of 1106 (X/1106 C1) and argue that, like the Great September Comet of 1882 (C/1882 R1), it evidently was a fragment of the comet recorded by the Chinese in September 1138. The 1106 sungrazer appears instead to have been the previous appearance of the Great March Comet of 1843 (C/1843 D1). With no momentum exchange involved, fragments of a Kreutz sungrazer breaking up tidally near perihelion are shown to end up in orbits with markedly different periods because their centers of mass are radially shifted by a few kilometers relative to the parent. The daylight comets of AD 363, recorded by a Roman historian, are accommodated in our computations as the first appearance of the Kreutz sungrazers after their bilobed progenitor's breakup. We link the 1843-1106-363 (Lobe I) and 1882-1138-363 (Lobe II) returns to perihelion by single nongravitational orbits and gravitationally with minor center-of-mass shifts acquired in fragmentation events. We also successfully model the motion of Aristotle's comet as the rotating progenitor that at aphelion split (at a few m/s) into the two lobes, the precursors of, respectively, the 1843 and 1882 sungrazers; and provide a 1963-1041-363 link for comet Pereyra (C/1963 R1). Material fatigue could contribute to sungrazers' fragmentation throughout the orbit, including aphelion. -- Continuing problems with the nongravitational law in orbit software are noted.

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Zdenek Sekanina, Rainer Kracht. 2022-07-01. The Great Comet of 1106, a Chinese Comet of 1138, and Daylight Comets in late 363 As Key Objects in Computer Simulated History of Kreutz Sungrazer System. https://arxiv.org/abs/2206.10827

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