Subject: Re: 4/11 *Black Box*
From: rjohnson@vela.acs.oakland.edu (R o d Johnson)
Date: 1991-04-15, 15:36
Newsgroups: alt.tv.twin-peaks

In article <1991Apr15.153824.23535@watserv1.waterloo.edu> alternat@watserv1.waterloo.edu (Ann Hodgins) writes:

> >Actually this has bugged me for a while.  What makes the moon light?  -
> >reflecting sun light. What causes the dark side?  - as far as I know it
> >is the earth interfering with the light getting to the moon. 

Aha, I see the problem.  No, what causes the dark side is simply the
fact that one source of light can't light up both the front and back
sides of an object.  Bring an orange near a lamp and you'll see--the
side facing away from the light is dark.

Now hold the orange at arms length and spin slowly, observing how much
of the part you can see is lit up. When the orang is directly between
you and the lamp, none of the hemisphere you can see is light.  That's
"new orange".  When it's at a 90 degree angle from the light, it's
"quarter orange".  When it's at its farthest point from the light,
it's "full orange" except that you're blocking the light and causing
an "orange eclipse."

Anyway, half the moon/orange is always light, and the phases are
caused by our point of view with respect to the light part.

-- Rod Johnson * rjohnson@vela.acs.oakland.edu * (313) 650 2315 "Poetry ends like a rope" --Jack Spicer