Phases in Space
Date: 1999 - 2000
From a two mile long space station orbiting halfway
between the earth and the moon, what would the phases of the earth and
moon look like? Would the sun, earth, and moon appear to rise and set?
I need to know this for a book that I am writing with a junior member of
my astronomy club.
You can probably do a better job of answering this question than I can
because you can draw a picture and see for yourself exactly what is
Draw the sun and the earth, and make the side of the earth that faces
away from the sun dark. Draw two big circles around the earth (but
make the circles small compared to the distance between the earth and
sun) and put a little paper disk representing the space station
somewhere on the inner circle. Put a little paper disk representing
the moon somewhere on the outer circle. Make both paper disks dark on
the side facing away from the sun. Move the space station and the moon
around on their orbits, always keeping their dark sides facing away
from the sun, and you can see how the moon and earth will look to
someone on the space station.
Now rotate the space station and see how the sun, moon, and earth rise
and set from the viewpoint of someone on the space station.
Have a nice book.
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Update: June 2012