Kenneth wrote:
> Tim Riley <timothyrileyatnetscapedotnet> wrote:
> 
>>The earth reflects approximately 39% of the
>>sunlight that hits it (which is where the title of Vangelis' album
>>"Albedo 0.39" comes from).
>
> I had actually forgotten about that!  Thanks. But I seem to remember reading
> somwehere that the moon's surface material is VERY dark...which would
> explain why the "darK" part of the moon seems almost black, compared to
> it's much brighter half-moon shape.  In other words, the dark half is
> reflecting much less than 39%. Wheras, the sun is SO bright that it makes
> the moon's intrinsically-dark material positively GLOW with brilliance! ;-)
> So I would *assume* that the albedo isn't contributing very much to the
> bright half's appearance, relatively speaking.

Actually I'd say that the primary reason why the contribution to the 
bright part is negligible is that only a very small part of the light 
reflected by the earth hits the moon (but the moon's low albedo plays a 
role too (it's 12%, according to Google's first hit 
<http://www.asterism.org/tutorials/tut26-1.htm>)). Keep in mind that the 
earth's albedo being 39% doesn't mean that 39% of the light that hits 
the earth is reflected to the moon. It is reflected in all directions, 
and the moon only covers a very small range of directions.

  -Christian

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