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arXiv · 2005.07131

Hierarchical Eclipses

Emil Khalisi·Joachim Gripp
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Abstract

The obscuration of a celestial body that covers another one in the background will be called a ``hierarchical eclipse''. The most obvious case is that a star or a planet will be hidden from sight by the moon during a lunar eclipse. Four objects of the solar system will line up then. We investigate this phenomenon with respect to the region of visibility and periodicity. There exists a parallax field constraining the chances for observation. A historic account from the Middle Ages is preserved that we analyse from different viewing angles. Furthermore, we provide a list of events from 0 to 4000 AD. From this, it is apparent that Jupiter is most often involved in such spectacles because its orbit inclination is small. High-inclination orbits reduce the probability to have a coincidence of an occultation of that object with a lunar eclipse.

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Emil Khalisi, Joachim Gripp. 2020-05-13. Hierarchical Eclipses. https://arxiv.org/abs/2005.07131

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