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One point about a lunar eclipse is that it looks the same from wherever you see it on earth. Everyone will see the eclipse start at the same time and finish at the same time. That being the case, you can get a reasonable estimate of Time from noting when the shadow of the earth is, say, half-way across the moon. I would say the accuracy of estimating Time this way is probably as good as the average 'lunar'. In fact, a lunar eclipse is a Moon-Earth lunar, of sorts, but nobody seems to have thought about it this way....

Geoffrey Kolbe