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Where’s the moon? First quarter

A first quarter moon rises at noon and is high overhead at sunset. It sets around midnight.

Karl Diefenderfer caught a first quarter moon at sunset on June 12, 2016.

Karl Diefenderfer caught a first quarter moon at sunset on June 12, 2016. “Such a lucky shot,” he wrote. Thanks, Karl!

A first quarter moon shows half of its lighted hemisphere – half of its day side – to Earth.

First quarter moon comes on June 12, 2016 at 0810 UTC (3 a.m. CDT). Translate to your timezone.

We call this moon a quarter and not a half because it is one quarter of the way around in its orbit of Earth, as measured from one new moon to the next.

This moon appears half-lit to us, and half moon is a beloved name (although not an official one). Still, it’s good to recall that the illuminated portion of a first quarter moon truly is just a quarter. On the night of first quarter moon, we see half the moon’s day side, or a true quarter of the moon. Another lighted quarter of the moon shines just as brightly in the direction opposite Earth!

A first quarter moon rises at noon and is high overhead at sunset. It sets around midnight.

First quarter moon comes a week after new moon. Now, as seen from above, the moon in its orbit around Earth is at right angles to a line between the Earth and sun.

When the first quarter moon sets around midnight, the sun is below your feet. See? Good time to get a 3-D sense of the moon as a world in space, always half-illuminated by the sun. Animation created from images of setting first quarter moon, June 12, 2016, by Peter Lowenstein in Mutare, Zimbabwe.

When the first quarter moon sets around midnight, the sun is always below your feet. Good time to experience the moon and Earth as worlds in space, always half-illuminated by the sun. Setting first quarter moon – night of June 11-12, 2016 – by Peter Lowenstein in Mutare, Zimbabwe.

As the moon orbits Earth, it changes phase in an orderly way. Follow these links to understand the various phases of the moon.

Understanding Moon Phases
Waxing Crescent
First Quarter
Waxing Gibbous
Full Moon
Waning Gibbous
Last Quarter
Waning Crescent
New Moon

Deborah Byrd

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