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The total eclipse of the Moon on December 21, 2010 made a great big splash in articles such as this one, because this was supposedly the first total lunar eclipse to coincide with the winter solstice since the year 1554. Before we check the accuracy of this claim, let's eliminate some ambiguity and call this the December (or southern) solstice. After all, the December (southern) solstice is the Southern Hemisphere's summer solstice.
Fact versus Factoid
I trust that most people know the definition of the word fact, so I'll take that as a given. But I have a feeling that the meaning of factoid isn't quite as well understood, so I'll quote the definiton from my Random House Webster's Unabridged Dictionary: something ficticious or unsubstantiated that is presented as fact, devised especially to gain publicity and accepted because of constant repetition.
Last December Solstice Total Lunar Eclipse in 1554?
First of all, let's relax the definition of the word "coincide" to mean that the two events can fall less 24 hours apart from one another. That means the total lunar eclipse and the December solstice may - or may not - occur on the same calendar date, depending upon one's time zone. Be that as it may, we'll say the two events coincide as long as they're less than 24 hours apart.
Using the criteria as defined by the previous paragraph, the total lunar eclipse coincided with the December solstice in the year 2010. But how about in the year 1554?
Is It Really "according to NASA?"
Almost all the articles asserting that 1554 staged the last December solstice total lunar eclipse before 2010 tagged along the words "according to NASA." However, I invite you to check out the NASA Eclipse Web Site page listing all the lunar eclipses for the years 1501 to 1600.
In 1554, both lunar eclipses were partial, not total. What's more, the lunar eclipse fell on December 9, 1554, whereas the solstice took place on December 12, 1554 (source: page 139 of the 2nd edition of Astronomical Tables Of The Sun, Moon And Planets by Jean Meeus). As a reminder, the Julian - not the Gregorian - calendar was in use in 1554.
No matter how you cut it, no total lunar eclipse fell on the December solstice in 1554!
Last Occurrence of Total Lunar Eclipse & December Solstice?
Again, if we refer to years whereby the total lunar eclipse and the December solstice take place less than 24 hours apart, the last time the two events coincided (before 2010) was in December 1703. The next time will be in December 2029. If, for some reason, we want to insist that the two events must fall on the same calendar date by Universal Time, the next time will be December 21, 2094, whereas the last time was December 21, 1638.
At Last, the 456-Year Puzzle Solved!
Congratulations to bikenbeer, who seems to have solved the mystery:
2094-1638 = 456
Apparently, it means the 2010 production is the only December 21 solstice total lunar eclipse (by Universal Time) within a 456 year window. Whew!!!
December 2010 Feature * February 2011 Feature
copyright 2010 by Bruce McClure
|Five Thousands Years of Lunar Eclipses|