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This is an odd question about the moon. Here is a picture of the earth-moon system.
As you can see, there is a new moon.

My question: where is the sun???

If it’s on the left, then why is the Earth dark on the left? The Moon can’t
be blocking the light, because that would be an eclipse.

If the sun is on the right, then why is the Moon dark on the right? The Earth
can’t be blocking the light, because that would be an eclipse as well!

One of my girlfriend’s friends is an astrophysics student, but she didn’t know
the answer. No-one I know can tell me the answer!


After asking the good people of,
this is an answer I received:

We don’t [see the new moon at night]. A New Moon is only visible at Dusk — as
again should be obvious from the fact that a New Moon (taken to be no more than two
days after minimum illumination) must be within 24 degrees of the Sun (360 degrees
divided by the 29.5 day lunar month means the Moon moves about 12 degrees per day
across the sky.)

That of course, makes perfect sense. Now my brain can have a rest! This is the
correct diagram, with the Sun included.