In article <1210290695@[EMAIL PROTECTED]
>, Wayne Throop <throopw@[EMAIL PROTECTED]
>
writes
>:: If a planet has multiple moons, all large enough to be visible, as
>:: discs, from the surface (through the atmosphere), i.e. unlike the
>:: moons of Mars, will they all be in the same phase at the same time,
>:: i.e. full, waning, new, waxing?
>::
>:: If not, how does it work. Is there some kind of essay I can read, or
>:: a brief educational animation I can watch, or something?
>
>: You can test it yourself near Sunset on a fine day by sitting in an
>: open space with a number of footballs spread around you.
>
>Round balls are better. Or are these them european footballs?
>I'd probably recommend, say, baseballs. Or tennis balls. Or oranges
>and/or grapefruits. But whatever. Whatever's handy, I suppose.
>
>In any event, you don't need sunset. Use a darkened room, an
>unsheilded lightbulb placed at some location behind you, and balls at
>various locations in front of you. Move the lightbulb and the balls
>around as needed. Arguably easier than mvoing the earth and/or the sun.
>
>Oh... well, you turn the lightbulb on, of course.
>
>
>Wayne Throop throopw@[EMAIL PROTECTED]
http://sheol.org/throopw
After my brother in law had trouble explaining exactly why the moon has
phases to his son, I remember spending more time than I bargained for
with a black permanent marker colouring in half of a ball. I can't
actually remember what sort of ball, but I think that if it wasn't a
tennis ball it was around that size. The result wasn't as moon-like as I
expected, I think because you are close enough to see a ball and not an
apparently flat circle, but you could get the idea.
--
A.G.McDowell
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