Our Moon is always up there and one half is always illuminated by sunlight and the nighttime half is in its own shadow, even though we don’t always see that.

I post a lot about the Moon and I’m hardly alone in being fascinated by it. You may have an astronomical interest in it, or maybe a more Romantic interest. Either way, you probably only think of the view of the Moon from Earth and not the other way.

Right now we are in the last quarter phase when we see half the moon’s day side, and half its night side. I recently discovered that the shadow line dividing day from night is called the lunar terminator.

Here’s another way to view the moon, if only theoretically. If you were on the moon now while it is in its last quarter phase, as it is today, and you were looking back at Earth, you’d see the Earth at its first quarter phase.

Perhaps some day, a lunar-living blogger will post regularly about the phases of the Earth.



As seen from the moon, the terminator on the first quarter Earth depicts sunrise, as the first quarter Earth waxes toward its full phase.