Abstract
PENUMBRAL LUNAR ECLIPSES.—The January issue of L'Astronomic, contains an article by M. Gaetan Blum on this subject. Consideration of these eclipses is necessary to make the theory complete; when they are included there must be one lunar eclipse at every passage of the sun through either node, and there may be two. The almanacs as a rule do not give predictions of penumbral eclipse, but they have done so occasionally by some caprice. Eclipses in which the moon penetrates deeply into the penumbra are quite readily observable, it being obvious that a portion of the moon is dimmed by a smoky veil. There will be an eclipse of this kind on December 19 next, full moon being at 6h,/sup> 8,sup>m A.M., so that it will be visible in Great Britain. The least distance of the moon's limb from the umbra will be less than a minute of arc. The article notes that the phenomenon is rendered more noticeable if the moon's light is weakened by reflection at an unsilvered glass surface.
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Our Astronomical Column. Nature 117, 463 (1926). https://doi.org/10.1038/117463a0
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DOI: https://doi.org/10.1038/117463a0