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Moon Phases

Photo Credit: Dan Bush
Tonight | Oct 05, 2013

Understanding moon phases

Why does the moon seem to change its shape every night? Remember that the moon is a world in space – with a day side and a night side.

Photo Credit: James Jordan
Tonight | Oct 03, 2013

Understanding waning crescent moon

A waning crescent moon is sometimes called an old moon. It’s seen in the east before dawn.

Photo Credit: Yourdon
Tonight | Feb 25, 2013

Understanding full moon

You know it when you see it, but what makes a full moon full?

Photo Credit: Waiferx
Tonight | Jul 26, 2012

Understanding first quarter moon

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

Photo Credit: Missouri Skies
Tonight | Jul 23, 2012

Understanding waxing crescent moon

When you see the moon as a slim crescent – in the west after sunset – it’s a waxing moon. Is that Earth’s shadow on the moon? No, it’s the moon’s own shadow.

Last quarter moon via Annie Lewis
Tonight | Jul 10, 2012

Understanding last quarter moon

A last quarter moon looks half-illuminated. It rises around midnight, appears at its highest in the sky at dawn, and sets around noon.

Photo Credit: Missouri Skies
Tonight | Jul 06, 2012

Understanding waning gibbous moon

In the few days after full moon, you’ll often see a waning gibbous moon in the west in early morning, floating against the pale blue sky.

Photo Credit: Missouri Skies
Tonight | Jul 01, 2012

Understanding waxing gibbous moon

A waxing gibbous moon appears high in the east at sunset. It’s more than half-lighted, but less than full.

New moon: night side of moon facing Earth
Tonight | Mar 17, 2012

Understanding new moon

On the day of new moon, the moon rises when the sun rises. It sets when the sun sets. It crosses the sky with the sun during the day.