Once in a Blue Moon

La Luna Llena de Marzo, Luna Llena de Aries, Luna en Libra, Luna de la Primavera, Luna de Ostara o luna llena Pascual es la cuarta Luna Llena del año en el calendario Gregoriano:

The March 1999 issue of Sky & Telescope contains an article, "Once in a Blue Moon", concerning different "folk etymologies" for the expression "blue moon".

The earliest reference cited was from the Maine Farmers' Almanac for 1937. This states that:

The Moon usually comes full twelve times in a year,  three times in each season.  These moons were named by our early English ancestors as follows:

 Yule

Winter Moons:

   1 Moon after Yule

   2 Wolf Moon

   3 Lenten Moon

 First Day of Spring

Spring Moons:

   4 Egg Moon

   5 Milk Moon

   6 Flower Moon

 The Long Day

Summer Moons:

   7 Hay Moon

   8 Grain Moon

   9 Fruit Moon

 Summer's End

Fall Moons:

  10 Harvest Moon

  11 Hunter's Moon

  11 Moon before Yule

However,  occasionally the moon comes full thirteen times in a year.  So the "Blue Moon" can apparently be summarized as follows:

If there are four full moons during a given season of the year, the third full moon is considered to be the Blue Moon

... PERO, no así en el Calendario de 13 Lunas (13-Moon Calendar) Maya.

The Roman Calendar started with the vernal equinox and consisted of 10 months totaling 304 days. The months: Martius, Aprilis, Maius, Junius, Quntilis, Sextilis, September, October, November and December are the basis of our modern calendar system. The Roman Numa Pompilius (715-673 BC) introduced two additional months, January and February to increase the length of the year to 354 or 355 days. The Roman Calendar was eventually replaced by the Julian calendar in 46 BC. In 46 B.C. Romans used a 365 day year, but that ended when Julius Caesar took his armies into Egypt. There he learned about the Alexandrian calendar with its leap year cycle, which was more accurate than the current Roman calendar of 365 days. Caesar brought several astronomers to advise a calendar reform, which became the Julian calendar. This system was so accurate that only one day was in error in about every hundred years. In 1582 Pope Gregory XIII established his own commission to advise on calendar reform. By this time the calendar trailed the seasons by 11 days. His commission established the 4 year leap year calendar. As well as, changing New Years Day from March 25th to January 1st. The Gregorian calendar we utilize today was born.

http://prettypaganorwickedwitch.blogspot.com.es/2013/01/the-moon.html

hoppy easter

http://www.evolvingdoor.ca/miscarticles/bluemoon.htm
http://www.projectpluto.com/bluemoon.htm
http://www.socialphy.com/posts/off-topic/1868/13-Moon-Mayan-Synchronometer.html