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Skywatchers, get ready: The last "blue moon" for three years will occur on Friday, Aug. 31.

And, no, the moon will not actually be blue.

According to LiveScience's Stephanie Pappas, a blue moon was traditionally defined as the fourth full moon of a season. But since 1946, when a writer for Sky and Telescope either made a mistake or decided to make things simpler, it's come to mean the second full moon in a month.

A full moon occurs every 29.5 days, according to the Associated Press, and the last full moon occurred on Aug. 1.

The next blue moon won't occur until July 2015.

Those not able to see the blue moon on Friday due to weather or location need not worry: The Slooh Space Camera, a telescope that streams celestial events over the web in realtime, will be broadcasting the event. According to Space.com, two live feeds, one from Spain's Canary Islands and the other from the Prescott Obeservatory in Arizona, will be broadcast simultaneously.

For some, the Aug. 31 blue moon will take on additional significance as it's the day of the memorial service for Neil Armstrong, the first person to set foot on the moon. Armstrong died on Saturday at the age of 82.

Armstrong's family released a statement that day that said, in part:

“For those who may ask what they can do to honor Neil, we have a simple request. Honor his example of service, accomplishment and modesty, and the next time you walk outside on a clear night and see the moon smiling down at you, think of Neil Armstrong and give him a wink.”

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  • The full 'blue' moon appears in the sky

    The full 'blue' moon appears in the sky over Christmas decorations in the neighborhood where US President Barack Obama and the first family are vacationing in Kailua, Hawaii, on December 31, 2009. Normally in a calendar year there are 12 full moons but when there is a 13th in the calendar year it is called a Blue Moon AFP PHOTO/Jewel SAMAD

  • Istanbul, Turkey. (CREDIT: <a href="https://twitter.com/AltugArsoy" target="_hplink">@AltugArsoy</a>)

  • Blue moon over Paris, France. (CREDIT: <a href="https://twitter.com/RhinocerosVert" target="_hplink">@RhinocerosVert</a>)

  • Blue moon....well, orange moon.

    <a href="http://www.huffingtonpost.com/social/Leith_AdieStahl"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1302668916/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Leith_AdieStahl">Leith AdieStahl</a>:<br />

  • Southwest Australia (CREDIT: <a href="https://twitter.com/Coopera89/status/241668142449975297" target="_hplink">@Coopera89</a>)

  • Bethesda, MD (CREDIT: <a href="https://twitter.com/jasonmc100/status/241688577120010240" target="_hplink">@jasonmc100</a>)

  • Bloomfield, NJ. (CREDIT: <a href="https://twitter.com/ivani217/status/241700749942329344" target="_hplink">@ivani217</a>)

  • (CREDIT: <a href="https://twitter.com/dash04/status/241698329489182720" target="_hplink">@dash04</a>)

  • The Blue Moon Down The Block

    <a href="http://www.huffingtonpost.com/social/Gigi820"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/Gigi820">Gigi820</a>:<br />

  • Blue moon

    <a href="http://www.huffingtonpost.com/social/jv8222"><img style="float:left;padding-right:6px !important;" src="http://images.huffingtonpost.com/aol_profile_img/3832877.png" /></a><a href="http://www.huffingtonpost.com/social/jv8222">jv8222</a>:<br />Picture by Jamie From Bloomfield NJ

  • Blue Moon August 31, 2012

    <a href="http://www.huffingtonpost.com/social/Kelby_Roberson"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1817589103/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Kelby_Roberson">Kelby Roberson</a>:<br />This photo of the "blue moon" was taken tonight, August 31, 2012, from eastern North Carolina, USA. You can find more pictures of this event on my facebook fan page- Kelby Roberson Photography.

  • Tokyo, Japan. (CREDIT: <a href="https://twitter.com/hiyo_otamanist" target="_hplink">@hiyo_otamanist</a>)

  • Blue Moon, August 2012

    <a href="http://www.huffingtonpost.com/social/playnotwork"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/674252744/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/playnotwork">playnotwork</a>:<br />Strasburg, VA

  • Unclear Blue Moon with the Street Lamp Light

    <a href="http://www.huffingtonpost.com/social/kdwr0920"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/kdwr0920">kdwr0920</a>:<br />New York City's Blue Moon Light

  • Blue Moon in WV

    <a href="http://www.huffingtonpost.com/social/Old_Crow_Wv"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1059706853/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Old_Crow_Wv">Old Crow Wv</a>:<br />Beckley, WV

  • "Blue Moon" August 31st, 2012

    <a href="http://www.huffingtonpost.com/social/Jonathan_LaPlante"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1375402082/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Jonathan_LaPlante">Jonathan LaPlante</a>:<br />"Blue Moon in Southern New Hampshire"

  • Blue Moon from Eastford, CT

    <a href="http://www.huffingtonpost.com/social/loringjane"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/loringjane">loringjane</a>:<br />Blue Moon as seen from Eastford, CT, USA

  • A real Bbue moon

    <a href="http://www.huffingtonpost.com/social/rdking"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1104046189/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/rdking">rdking</a>:<br />Taken from my yard in Austin Texas with an Infrared camera

  • Late Summer Full Moon in Aquarius (blue)

    <a href="http://www.huffingtonpost.com/social/OC_Surfer"><img style="float:left;padding-right:6px !important;" src="http://i.huffpost.com/profiles/2984399-tiny.png?20120331150208" /></a><a href="http://www.huffingtonpost.com/social/OC_Surfer">OC Surfer</a>:<br />August 29th in Portland, Oregon, using 14x optical zoom on a handycam.

  • From Fountain Colorado

    <a href="http://www.huffingtonpost.com/social/imikejr"><img style="float:left;padding-right:6px !important;" src="http://images.huffingtonpost.com/aol_profile_img/1646175.png" /></a><a href="http://www.huffingtonpost.com/social/imikejr">imikejr</a>:<br />Aug 31 2012 Blue Moon

  • Blue Moon. Grand Rapids, MI USA

    <a href="http://www.huffingtonpost.com/social/Phern_Sendin"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/100000367888241/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Phern_Sendin">Phern Sendin</a>:<br />I took this about ten minutes ago when the sky cleared. It's just absolutely gorgeous.

  • The blue moon 8/31/2012

    <a href="http://www.huffingtonpost.com/social/Ai-Ling_Yew"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/657461981/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Ai-Ling_Yew">Ai-Ling Yew</a>:<br />

  • Blue moon

    <a href="http://www.huffingtonpost.com/social/Tatyana_Gronback"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1007159961/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Tatyana_Gronback">Tatyana Gronback</a>:<br />

  • Blue Moon_North East Texas

    <a href="http://www.huffingtonpost.com/social/EFranze"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1567879819/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/EFranze">EFranze</a>:<br />Blue Moon_North East Texas

  • man and dog, once in a blue moon

    <a href="http://www.huffingtonpost.com/social/MartinSWilson"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1701260543/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/MartinSWilson">MartinSWilson</a>:<br />

  • Blue Moon over Nashville,Tn

    <a href="http://www.huffingtonpost.com/social/Cippin"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/100000102124890/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Cippin">Cippin</a>:<br />Blue Moon Over Nashville, TN

  • Blue Moon in Lakeland,Fl

    <a href="http://www.huffingtonpost.com/social/mabeldi9"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1208992031/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/mabeldi9">mabeldi9</a>:<br />

  • Blue moon in Aquarious

    <a href="http://www.huffingtonpost.com/social/CzechChick"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1198186299/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/CzechChick">CzechChick</a>:<br />Blue moon in Aquarious as reflected in the Lower Senate Park pool, Washington, DC

  • Blue Moon Peachtree City GA

    <a href="http://www.huffingtonpost.com/social/Jorge_Roman"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/100000766594695/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Jorge_Roman">Jorge Roman</a>:<br />Taken from my backyard in Peachtree city GA

  • Blue Moon over Lake Evans, Riverside, CA

    <a href="http://www.huffingtonpost.com/social/lovinbats"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/lovinbats">lovinbats</a>:<br />

  • Blue Moon over Chequamegon Bay on Lake Superior

    <a href="http://www.huffingtonpost.com/social/shutterwi"><img style="float:left;padding-right:6px !important;" src="http://images.huffingtonpost.com/twitter_profile_img/3833516.png" /></a><a href="http://www.huffingtonpost.com/social/shutterwi">shutterwi</a>:<br />Photographed with Canon 7D with Canon 100-400mm 5.6 IS lens. For more photos of the Chequamegon Bay Wisconsin region see http://shutterwi.com

  • Blue Moon August 2012

    <a href="http://www.huffingtonpost.com/social/Capricornjack83"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/590247999/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Capricornjack83">Capricornjack83</a>:<br />The view of the "Blue Moon" from Aurora, Colorado

  • Blue Moon over Bainbridge 8/31/12

    <a href="http://www.huffingtonpost.com/social/penfolds90"><img style="float:left;padding-right:6px !important;" src="http://images.huffingtonpost.com/aol_profile_img/3833538.png" /></a><a href="http://www.huffingtonpost.com/social/penfolds90">penfolds90</a>:<br />

  • Blue Moon over Grand Junction. Colorado 8/31/2012 sdw

    <a href="http://www.huffingtonpost.com/social/Shannon_Whittley"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/548421259/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Shannon_Whittley">Shannon Whittley</a>:<br />

  • Blue Moon & campfire

    <a href="http://www.huffingtonpost.com/social/lara9209"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/lara9209">lara9209</a>:<br />who could ask for anything more ??

  • Blue Moon

    <a href="http://www.huffingtonpost.com/social/gabrock21"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/gabrock21">gabrock21</a>:<br />

  • Blue Moon/ 8/31/2012

    <a href="http://www.huffingtonpost.com/social/gabrock21"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/gabrock21">gabrock21</a>:<br />

  • blue moon

    <a href="http://www.huffingtonpost.com/social/starkeye"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/731892089/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/starkeye">starkeye</a>:<br />Marina del Rey, Ca

  • bluemoon

    <a href="http://www.huffingtonpost.com/social/starkeye"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/731892089/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/starkeye">starkeye</a>:<br />starkeye photography, Marina del rey, Ca

  • Blue Moon Rising

    <a href="http://www.huffingtonpost.com/social/Tetsu_Ishikawa"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/Tetsu_Ishikawa">Tetsu Ishikawa</a>:<br />from Yokohama JAPAN

  • Full Moon over Dalsland,Sweden

    <a href="http://www.huffingtonpost.com/social/keith44"><img style="float:left;padding-right:6px !important;" src="http://i.huffpost.com/profiles/899224-tiny.png?20120520050910" /></a><a href="http://www.huffingtonpost.com/social/keith44">keith44</a>:<br />by gkr

  • Blue Note

    <a href="http://www.huffingtonpost.com/social/view_from_the_veranda"><img style="float:left;padding-right:6px !important;" src="http://i.huffpost.com/profiles/2226907-tiny.png?20111214113527" /></a><a href="http://www.huffingtonpost.com/social/view_from_the_veranda">view from the veranda</a>:<br />There was definitely a blue gleam in the Moons eye tonite.

  • Blue Cheese Moon

    <a href="http://www.huffingtonpost.com/social/Meggan_Wood"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/573591796/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Meggan_Wood">Meggan Wood</a>:<br />From Maricopa, AZ, 8-31-12 just before midnight. NexStar 5SE telescope, 40mm eyepiece w/ blue filter, Canon Rebel XSi.

  • From Maui

    <a href="http://www.huffingtonpost.com/social/C_Frank_Wolfe"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/C_Frank_Wolfe">C Frank Wolfe</a>:<br />

  • Blue Moon

    <a href="http://www.huffingtonpost.com/social/mrh219"><img style="float:left;padding-right:6px !important;" src="http://images.huffingtonpost.com/aol_profile_img/3834168.png" /></a><a href="http://www.huffingtonpost.com/social/mrh219">mrh219</a>:<br />Silver Lake, NY

  • "Blue Moon" over Lake Michigan

    <a href="http://www.huffingtonpost.com/social/Tyderyiem"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/Tyderyiem">Tyderyiem</a>:<br />The "blue moon" rises over Lake Michigan

  • Blue Moon Peeking At Me

    <a href="http://www.huffingtonpost.com/social/Cobalt_Blue_Roses"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/Cobalt_Blue_Roses">Cobalt Blue Roses</a>:<br />Blue was being coy...

  • A Redish Blue Moon

    <a href="http://www.huffingtonpost.com/social/millervic"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/611896263/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/millervic">millervic</a>:<br />

  • Blue Moon over the Golden Gate Bridge

    <a href="http://www.huffingtonpost.com/social/StevenGatlin"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1131296663/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/StevenGatlin">StevenGatlin</a>:<br />San Francisco Bay Area photographer Steve Gatlin captured this shot of the Blue Moon over the Golden Gate Bridge. August 31, 2012. http://GatlinPhotography.com

  • Friday, August 31, 2012 Blue Moon

    <a href="http://www.huffingtonpost.com/social/Al_Maslowski"><img style="float:left;padding-right:6px !important;" src="http://s.huffpost.com/images/profile/user_placeholder.gif" /></a><a href="http://www.huffingtonpost.com/social/Al_Maslowski">Al Maslowski</a>:<br />Alfred Maslowski 2012 Portland, OR, USA

  • Cloudy Blue Moon

    <a href="http://www.huffingtonpost.com/social/Mary_Jane_Washburn"><img style="float:left;padding-right:6px !important;" src="http://graph.facebook.com/1526970561/picture?type=square" /></a><a href="http://www.huffingtonpost.com/social/Mary_Jane_Washburn">Mary Jane Washburn</a>:<br />Photo taken in Farmington,NM by MJ Washburn

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