Silent
Posted: 08 October 2007 05:08 AM   [ Ignore ]
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From Rabelais, the Fifth Book of Gargantua and Pantagruel, ch. XLIII:

The seventh of Sienites {tr. error for Selenite}, transparent, of the Colour of a Beril, and the clear hue of Hymetian Honey, and within it the Moon was seen, such as we see it in the Sky, Silent, Full, New and in the Wain.

Silent? What an odd usage. But indeed here it is in the OED, obsolete now, of course.

Silent, a. and n.

5. a. Of the moon: Not shining. Obs.

a1646 J. GREGORY Posthuma (1650) 202 The most easie deliverie..is alwaies in the increas, toward and in the full of the Moon, and the hardest labors in the new and silent Moon.

Quite charming, I thought

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Posted: 08 October 2007 05:49 AM   [ Ignore ]   [ # 1 ]
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But how can we “see it in the Sky” if it’s Silent?

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Posted: 08 October 2007 06:10 AM   [ Ignore ]   [ # 2 ]
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We can “see” it because it occults stars.

And besides, the moon is never totally dark. Even at the exact instant of the new moon when no directly reflected sunshine is visible on earth, there is reflected earthshine off the moon. It is somewhat lighter than the background of space. And this relative darkness would have been more apparent in pre-20th century times when there was no light pollution to speak of and the sky was even blacker than we usually see it today.

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Posted: 08 October 2007 06:44 AM   [ Ignore ]   [ # 3 ]
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Correct me if I’m wrong, but ‘at the exact instant of the new moon ‘ it is broad daylight, isn’t it?
Only in the few days just before and after that moment the effect that Dave mentions occurs.

PS: I just checked some definitions of ‘new moon’ and it seems there is a difference between the popular meaning of the phrase (= when the moon starts becoming visible again) and the astronomers definiton (= when the moon is in conjunction with the sun).

From Wikipedia (via Webster’s online).
Traditionally, the lunar phase new moon begins with the first visible crescent of the Moon, after conjunction with the Sun. This takes place over the western horizon in a brief period between sunset and moonset. Therefore the time and even the day depend on the actual geographical location of the observer.
Currently, the new moon is defined by astronomers to occur at the moment of conjunction in ecliptic longitude with the Sun, when the Moon is invisible and a solar eclipse may occur. This moment is unique and does not depend on location. To avoid confusion with the traditional new moon, this may be called the dark moon.

Edit PPS: just realised that the criterion is that the sun and moon are vertically aligned. To some observers that may happen when the moon is just above the horizon while the sun has just set or hasn’t risen yet.

[ Edited: 08 October 2007 07:26 AM by Dutchtoo ]
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Posted: 08 October 2007 09:04 AM   [ Ignore ]   [ # 4 ]
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Correct me if I’m wrong, but ‘at the exact instant of the new moon ‘ it is broad daylight, isn’t it?

Yes, that’s right. The astronomical new moon is never visible--at least not to the naked eye; it’s always either obscured by sunlight or on the other side of the planet. In theory at least, you could pick it out with a telescope that gathers in enough light to make the earthshine-illuminated disc visible in daylight.

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Posted: 08 October 2007 10:31 AM   [ Ignore ]   [ # 5 ]
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Well, if we’re getting picky, it’s visible in silhouette during a solar eclipse.

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Posted: 08 October 2007 12:22 PM   [ Ignore ]   [ # 6 ]
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What Dave calls “earthshine” was called by Arthur C. Clarke “Earthlight”. It’s the title of one of his novels. He spelt it with a capital E --- because, presumably, Earth ifs the name of a particular heavenly body, like, say, Venus or Saturn --- whereas “moon” or “sun” are not.

(edited to correct alcohol-induced misspelling)

urp.

eructates gently a couple more times before stumbling to bed

[ Edited: 08 October 2007 12:25 PM by lionello ]
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