Lunchista has just noticed that it's New Moon right now. Rather than attempt to take a decent photo of it, though, I have cheated and availed myself of one from the marvellous Matt's Astronomy Site (thank you Matt).
Exactly two months ago a similar moon picture appeared in our local paper. You can tell a new moon from an old one because it's seen in the evening (not the morning) and (unless you are reading this in Argentina, ZA, NZ, Oz etc) the points of the crescent face left. The paper were puzzled about why the rest of the moon's surface was so well lit-up. It so happened that Lunchista knew the answer, and gave them a call.
The light on the non-crescent part of the moon is known as Earthshine. Whereas the crescent is being lit directly by the sun (but you knew that anyway, didn't you), the rest of the surface, if it is showing, is being bathed in faint light which has been reflected from the earth. Or more precisely, from the part of the earth which can be seen from the moon. Any part of the earth (particularly the 3/4 or so of it which are covered in sea) will reflect more light if it is covered in clouds than if there are none and the dark surface is showing.
Now it so happens that wherever on the planet you are, the new moon is always somewhere to your west. Here in the UK that means it is loitering over the Atlantic Ocean. It is therefore quietly telling you whether or not that ocean is covered in clouds. Just like a weather radar, in fact. The most common type of clouds over the Atlantic are the ones around a Low pressure system. Seen from the moon (or on the weather forecast if you can't afford the fare) it looks a bit like this:
In our part of the world these Lows tend to drift from west to east. That means a Low over the Atlantic will soon be over the UK, bringing clouds, wind and rain. Or at the very least it will be lurking out there ready to throw its rotten weather at anyone rash enough to set sail westwards.
Hence the sailor's warning from Sir Patrick Spens:
"I saw the new moon late yestreen,
Wi' the auld moon in her arms:
And if ye gang to sea, maister,
I fear we'll suffer harm."
Will there be earthshine this evening? If there is, will the dry weather finally break, and give Chateau Lunchista's garden a much-needed drink?
wow I did not know tha about the moon!
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