Year of the Comet
Comet C/2011 L4 (PANSTARRS)

PANSTARRS information

Comet C/2012 S1 (ISON)

ISON information

Glenn Chaple's Observing Basics

Lunar letters

September 2012: A First Quarter Moon offers observers countless targets, including two special letters.
Contributed by Glenn Chaple
Published: July 23, 2012
Glenn Chaple
First Quarter or half Moon — which is the correct name of the lunar phase that occurs one week after New Moon? Astronomers prefer the former while poets and dreamers opt for the latter. One of my goals as a middle school science teacher was to stamp “quarter Moon” into the impressionable young minds of my students. I had a tactic. I’d begin by saying, “Notice that First Quarter phase occurs when the Moon has traveled one quarter of the way around Earth since New Moon.” Then I’d add, “During First Quarter, we only see half of the one-half of the Moon that faces Earth. Half of one-half equals one quarter of the entire Moon.” Mission accomplished! Or so I thought.

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