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10 questions about September great lunar eclipse

An image by Fred Espenak ( http://www.mreclipse.com/ ) of a total lunar eclipse in 2004. Nations, like stars, are entitled to eclipse.  All is well, provided the light returns  and the eclipse does not become endless night.  Dawn and resurrection are synonymous.  The reappearance of the light is the same  as the survival of the soul. (Victor Hugo, 1862) 1. When will eclipse happen ? This is the fourth eclipse of a series called "tetrad" in the interval 2014-2015 and will "officially" occur on September 28th 2015. It is a fully total eclipse and you should consult question 3 to know the eclipse time for your place.  2. Where can it be seen? The following map (according to ref. 1) shows world regions where the eclipse will be visible (white areas correspond to full visibility) from P4 to P1. In Brazil, the entire eclipse will be visible. The same is valid for West Europe and East United States. The difference, however, is that, whil...

Photometry of the moon during the penumbral eclipse of October 2013.

Fig. 1 Moon at two different moments: during the penumbral eclipse (October 18 2013) and just after the eclipse end. S ome amateur astronomers complained about the popular interest during the last penumbral eclipse of the moon (Oct 18/13). With reason, they claimed that this eclipse would not be worth observing. The effect of moon darkening was very weak and the phenomenon would pass unnoticed had we not be previously informed by several internet sources. However, astronomy is an empirical science and it is usually made of occurrences with insignificant effects. Here we present a small report of a possible analysis of the light profile of the moon during this eclipse. Although some darkening is apparent in Fig. 1, we would like to make the difference "explicit" by image and quantitative analysis . Perhaps our approach could be used during other eclipses, or a systematic application of it could help the study, for instance, of more subtle variations of brightness dur...