wiki Word: lunar phases or lunar cycles

Definition: The appearance of the moon at different points along its orbit. A lunar phase is what we see of the moon at different angles.

There are many phases of the moon. When a new moon is occuring you can't see any of the moon. When a full moon occur you can see all of it. Halfway between a new and full moon we can see half of the illuminated half of the moon or a quarter of the moon. First quarter occurs as the moon moves from new to full. The third or last quarter occurs when the moon is moving from full to new. Between the new and quarter moons only a small fraction of the moon is illuminated. We call this a crescent moon. Between the quarter and full moon a larger fraction of the moon is illuminated. We call this a gibbeous moon. When the moon moves from new to full, it becomes more illuminated and we call this waxing. When it moves from full to new, it is getting less illuminated and we call this waning.

We have been doing moon observations for a few days and we need to know the different phases the moon goes through so we can see the change in the month it takes to complete its cycle. WE also learned that the cause of tides is the Moon's gravity pull on the Earth's oceans.

SOURCES:"Lunar Information". Pagan Institute Report. 5/2/08 <http://paganinstitute.org/PIR/lunar_info.html>.

Miles, Kathy. "Why Does The Moon have Phases". Starry Skies. 5/4/08 <http://starryskies.com/The_sky/events/lunar-2003/phases.html>.

 "Moon Phase". Lunar and Planetary Institute. 5/9/08 <http://www.lpi.usra.edu/education/skytellers/moon_phases/about.shtml>. 

Knopf, Alfred A., Field Guide to the Night Sky, Toronto, Canada, Alfred A. Knopf inc., 1991, The Solar System p. 635-637

Chisolm, Jennifer ed, The Complete Idiot's Guide to Astronomy Third Edition, Indianapolis, Indiana, Marie Butler-Knight, 2004, Part one: Our Place in Space p. 6

Knowles, Marianne, ScienceSaurus: A Student handbook, Wilmington, MA, Great Source Education Group, 2006, p.235
 Pasachoff, Jay M, Ph. D, Astronomy, Boston, Massachusetts, Pearson Prentice hall, 2005, p. 21-23

COOL SITES TO EXPLORE

http://spot.colorado.edu/~underwod/apas1110/moon.html

http://zebu.uoregon.edu/ph121/images/lunarphases.mpg