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arXiv · 1506.01402

Was Comet C/1945 X1 (du Toit) a Dwarf, SOHO-Like Kreutz Sungrazer?

Zdenek Sekanina·Rainer Kracht
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Abstract

The goal of this investigation is to reinterpret and upgrade the astrometric and other data on comet C/1945 X1, the least prominent among the Kreutz system sungrazers discovered from the ground in the 20th century. The central issue is to appraise the pros and cons of a possibility that this object is --- despite its brightness reported at discovery --- a dwarf Kreutz sungrazer. We confirm Marsden's (1989) conclusion that C/1945 X1 has a common parent with C/1882 R1 and C/1965 S1, in line with the Sekanina-Chodas (2004) scenario of their origin in the framework of the Kreutz system's evolution. We integrate the orbit of C/1882 R1 back to the early 12th century and then forward to around 1945 to determine the nominal direction of the line of apsides and perform a Fourier analysis to get insight into effects of the indirect planetary perturbations. To better understand the nature of C/1945 X1, its orbital motion, fate, and role in the hierarchy of the Kreutz system as well as to attempt detecting the comet's possible terminal outburst shortly after perihelion and answer the question in the title of this investigation, we closely examined the relevant Boyden Observatory logbooks and identified both the photographs with the comet's known images and nearly 20 additional patrol plates, taken both before and after perihelion, on which the comet or traces of its debris will be searched for, once the process of their digitization, currently conducted as part of the Harvard College Observatory's DASCH Project, has been completed and the scanned copies made available to the scientific community.

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Zdenek Sekanina, Rainer Kracht. 2015-09-10. Was Comet C/1945 X1 (du Toit) a Dwarf, SOHO-Like Kreutz Sungrazer?. https://doi.org/10.1088/0004-637x%2F815%2F1%2F52

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