Tag Archives: crescent

The Phases of the Moon in Song

Phases of the moon

Carol-Irene Southworth, a student in Professor B’s Solar System class at the University of California at San Diego, wrote and recorded the following song describing the phases of the Moon.  If you want to play along, the chords are just C and F, in this case played on the ukulele (according to Woody Guthrie, “if you play more than two chords, you’re showing off”).

Listen here [4:18m]:

Download here [5.2 Mb]: http://pono.ucsd.edu/~adam/astrofacts/southworth_moonphasesong.mp3

Lyrics are below!

What’s the facts:

Over the course of roughly a month, the part of the Moon that is illuminated goes through a regular cycle of phases.  Starting from dark new moon phase, the Moon gradually brightens, or waxes, through waxing crescent, first quarter, waxing gibbous and finally to a bright full moon phase 14 days later.  The Moon then dims, or wanes, over the next 14 days, going through waning gibbous, third quarter, waning crescent and finally dark new moon again.  This cycle is due to the relative orientation of the Sun, Moon and Earth, and the dark portions of the Moon are always caused by its own shadow shielding the Sun’s rays.  New moon phase happens when the Sun, the Moon and the Earth are in a line, so that the far side of the Moon we can’t see is lit up.  Full moon phase happens when the Sun, the Earth and the Moon are in a line, so we see the sunlit side of the Moon.  The other phases occur in between these two alignments, which are also called syzygy.

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Making Friends with the Night Sky: The Waxing Crescent Moon

The waxing crescent - the start of the lunar cycle

The waxing crescent - the start of the lunar cycle

Maui astronomer Harriet Witt describes the waxing crescent moon –  the first phase in the lunar cycle – and Earthshine.

Listen here [3:00m]:

Download here [7.3 Mb]: ftp://space.mit.edu/pub/ajb/radiopio/astrofacts_090722_mfns-mooncrescent.mp3

What’s the facts:

The waxing crescent is the first phase in the new Moon to new Moon lunar cycle.  You can catch it by looking toward the western sky early in the evening; there you will see a bowl-shaped sliver pointing toward the setting Sun, following it down to the horizon.  The opposite side is darker but not completely dark – it is faintly lit up by sunlight reflected from the Earth’s surface, called Earthshine.  The origin of Earthshine was first figured out by Leonardo Da Vinci in the 1500s; scientists now use Earthshine to track global cloud coverage and variations in the Earth’s climate. The waxing and waning crescent phases are the best time to observe Earthshine, so enjoy our spotlight on the Moon!

Original air date 22 July 2009.