# Illuminated Part of the Moon and Its Orientation with the Sun

**URL:** <https://boards.straightdope.com/t/illuminated-part-of-the-moon-and-its-orientation-with-the-sun/637468>\
**Category:** Factual Questions\
**Created:** [October 11, 2012, 10:46pm UTC](https://boards.straightdope.com/t/illuminated-part-of-the-moon-and-its-orientation-with-the-sun/637468 "2012-10-11T22:46:46Z")\
**Posts on this page:** 1\
**Page:** 2

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**Author:** ![Chronos](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/chronos/32/134_2.png) [@Chronos](https://boards.straightdope.com/u/Chronos)\
**Post date:** [October 13, 2012, 2:49pm UTC](https://boards.straightdope.com/t/illuminated-part-of-the-moon-and-its-orientation-with-the-sun/637468/21 "2012-10-13T14:49:07Z")

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> [@](#):
>
> If I’m understanding correctly, this is happening because you tend (at least I do) to believe that the sun and the moon are at about the same distance from the earth, meaning that the triangle composed of the centers of the earth, sun, and moon is isosceles. But they’re not, and the sun is always “behind” the moon in some sense, which would mean that the line you create from the moon should generally point father back, away, from you than it would be if that triangle were in fact isosceles.

That would change the phase, but wouldn’t change the orientation.

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