Relax, the world won't end on Dec 21, 2012

Even if that is what Mayans predicted, errors mean it would have happened by now

By Andy Ho, The Straits Times, 13 Oct 2012

TODAY is exactly 10 weeks to Dec 21, 2012, which doomsayers say is the end of the world.

This they deduce from the fact that a particular Mayan calendar written to begin in 3114BC just stops after 5,125 years, specifically on Dec 21, 2012.

That date also happens to be the winter solstice, which has the shortest day and longest night of the year in the Northern Hemisphere.

As a prophecy, it hinges on the fact that the Sun orbits around the centre of the galaxy which is 28,000 light years away from it.

The galaxy is so large that the Sun traversing 7.6 billion km a year still takes 250 million years to complete one orbit around the galactic centre, which is a giant black hole with the mass of a million suns or so.

Believers say that the Sun will be nearest to the galactic centre this Dec 21, with the Earth, Sun and galactic centre forming a straight line. They say this has not happened for 25,776 years.

Their argument is that the fact it will be the winter solstice when the Earth, Sun and galactic centre's black hole are aligned means that the Earth will be subjected to massive gravitational forces, which will trigger a cataclysm.

The ancient Mayan civilisation which extended over southern Mexico, Guatemala, Belize, El Salvador and some of Honduras, however, never made such a claim. There is no record the Mayans ever saw cataclysmic perturbations to our daily lives this Dec 21.

Actually, both winter and spring solstices in 1998 saw this alignment as well, according to Mathematical Astronomy Morsels V (2009) by Jean Meeus, after whom Asteroid 2213 was named Meeus in 1981. Yet no cataclysms occurred on Earth on both dates.

What's the science?

STILL, is there reason to think that the alignment will generate extreme gravitational effects on the Earth?

Gravity falls exponentially with distance. As it is just 150 million km away, the Sun exerts more gravity on the Earth than the far denser galactic centre that is 265 quadrillion km away.

In other words, because of its much greater distance, the pull of the latter's gravity on the Earth is several hundred million times weaker than that of the Sun.

What about the effect of that gravity on the tides anyway? Won't an astronomical alignment cause giant tsunamis on Earth? Tides are the result of just one aspect of gravity - that of shearing or stretching - which is but a tiny portion of total gravitational forces. Since the galactic centre's gravitational pull on the Earth is insignificant compared to that of the much smaller Sun, its shearing aspect (which causes the tides) is even less. So expect no tsunamis.

Finally, the solstice has nothing to do with the stars and the galaxy per se. It is simply the day on which the Earth's North Pole is tipped farthest away from the Sun, which will thus appear at its lowest in the sky for the year.

Even during their civilisation's classic period (AD250 to AD900) when they built great cities that were later abandoned for unknown reasons, the Mayans paid no attention to solstice or equinox. They also did not write about the galaxy (Milky Way) at all.

They did terminate the calendar this Dec 21 (on two stone inscriptions) but it is unlikely they did so knowing it would be the 2012 winter solstice - because it would require them to have understood what is called the "precession" of the Earth too.

There are no records to indicate the Mayans ever grasped this phenomenon first identified by the Greek astronomer Hipparchos in the 2nd century BC.

Precession refers to the change in the orientation of the axis of the Earth regarded as a rotating body. As it rotates on its own axis once a day, the Earth's axis (imagined as going through the North and South Poles) itself also rotates slowly by one degree in precisely 71.6 years. Thus the Earth's own axis itself makes a complete rotation of 360 degrees in 25,776 years, which is precession.

To picture what precession looks like, think of a top spinning on the ground. As it slows down, its top end wobbles in a circle more and more until it finally topples over. That wobbling which traces out a circle is precession.

The Earth also behaves like a spinning top because it is tilted at 23.5 degrees to the horizontal plane while also being fatter at the Equator by 43km in diameter than between the poles.

The Sun's gravity tries to pull the equatorial bulge of the spinning Earth down to the horizontal plane. This pull is what causes the Earth to wobble very slightly such that it will take 25,776 years for the wobbling axis of the Earth to make a full circle of 360 degrees.

Unless the Mayans also knew all this about precession, they would not have been able to place the Sun as being nearest the galactic centre among the stars for the first time in 25,776 years on the 2012 winter solstice.

Of course, five cycles of 5,125 years do make for 25,625 years - near enough to 25,776 years - although no Mayan record mentions five cycles at all.

Instead, the Mayans said that the gods failed thee times in creating the world, succeeding only on the fourth attempt, when humans were first placed here.

The third version of the world was ended after 5,125 years of failed existence, they said, when the present world began on Aug 11, 3114BC using the Gregorian calendar.

On the Mayan calendar which was written to run from Aug 11, 3114BC, or Creation Day, each date was represented with a string of numbers, say 0.0.0.1.5, the numerals being read from right to left designating by cycles - like a car odometer - the number of days in ever larger chunks of (basically) 20 after Creation Day.

This Dec 21 will be the Mayan date of 13.0.0.0.0, which simply says that 13 cycles of 144,000 days (or 1x20x18x20x20) have been completed since Creation, with the next day being 13.0.0.0.1, of course. (See below.)

What archaeology says

BUT why did it stop at 13.0.0.0.0? If, in fact, it did not, it would be nice to see a copy of the Mayan calendar that went beyond it. Indeed, in May, Boston University archaeologists reported a discovery by their undergraduates on a field trip of a brightly painted mural in the ruins of a city in the Guatemalan rainforest. Dated to AD800, the mural included a calendar in black and red that went up to 17.0.0.0.0 - or 1577 years beyond 2012 - bringing us to AD3589. This proves that the Mayans did not routinely think of the calendar as terminating on 13.0.0.0.0 per se.

At any rate, up until this painted calendar was unearthed, there were only two stone inscriptions ever found that showed the calendar ending this Dec 21. And now the second one, reported just this June, offers a reason why the date was chosen: politics.

Guatemalan archaeologists reported in June their discovery of a 1,300-year-old inscription carved on a stone staircase in the ruins of another city located in a rainforest in Guatemala. One of the longest ancient Mayan texts ever discovered, the inscription of 264 hieroglyphs commemorates the visit of King Fire Claw to the city on 13.0.0.0 (with three zeros) which was Jan 29, AD696.

Having just lost a battle with an enemy nation, the king was on a royal visit from the capital to assure this city's denizens that he would eventually win the war, so that his kingdom would last even unto 13.0.0.0.0, (with four zeros), the additional zero adding 1,316 solar years from the day of his visit even unto Dec 21, 2012.

Therefore, the mention of this Dec 21, 2012 was simply a political statement the king issued to allay the fears of his beleaguered subjects. It was a rhetorical device to project retrodictively from the distant future back into the real here and now for them in AD696.

If so, 13.0.0.0.0 was really about mastery and perpetuity, not calamity and expiry. The ancient Mayans would have assumed it was just going to be 13.0.0.0.1 the following day, when the Sun would rise as it has always done.

An interesting wrinkle to all the New Age doomsday talk is that Dec 21, 2012 may not even be 13.0.0.0.0 itself. Professor Gerardo Aldana, a Mayanist at University of California at Santa Barbara, has argued that Dec 21 may be at least 60 or even 100 days too late.

In Calendars and Years II: Astronomy and Time In The Ancient and Medieval World (2010), he notes that Mayanists marked significant historical events in time using astronomical signs. Today's scholars correlate their dates to the Gregorian ones by using astronomical, radiocarbon and archaeological evidence.

Prof Aldana shows, however, that the Mayans may have made significant errors in their astronomical markers when they noted specific dates by what they thought were movements of Venus. In one instance, they timed a specific historical event by what they thought was Venus which has a regular orbit but which science now knows to have been but a meteorite, which has a random trajectory.

Prof Aldana argues that the correlation of the Mayan calendar with the Gregorian one may be up to 100 days off. If correct, this would put 13.0.0.0.0 in mid-September 2012.

If so, the putative end of the world came and went without a whimper.

At any rate, the sum of the evidence from both astrophysics and archaeology says that the end of the world is not nigh at all.

How the Mayan calendar works

IF A car odometer reads 0.0.0.0.0.5, it has been driven only 5km. The first digit on the right goes up to 9 and, at 10km, it clicks back over to zero. Now the dial to its left shows 1, making it 0.0.0.0.1.0 or 10km travelled. Each time you travel 10km from now on, the first digit goes back to zero and the second digit climbs up step by step to 9, at which point it reads 0.0.0.0.9.9 for 99km. The next 1km sees the third numeral click over to 1, showing 0.0.0.1.0.0 for 100km. And so on in chunks of 10, until you come to 1.0.0.0.0.0 for 100,000km when all are reset to zero to start over again.

The Mayan calendar is like this but goes up in chunks of 20 (with one exception). Its basic unit is K'in or day. The next is Winal, a group of 20 days. So 1 Winal is 20 days. When written as a date, K'in goes up to 19 only. When it reaches 20, like the odometer, it clicks over to zero, and the dial to its left for Winal turns to 1, since 1 Winal is 20 days completed. The Winal dial goes up to 17 only. When 18 Winal, 18 cycles of 20 days, are completed, it clicks over to zero and the dial to its left now shows 1 for 1 Tun, or 18 Winal or 18x20 days or 360 days. After this, all units are in chunks of 20, so reading from right to left, the numerals indicate cumulatively: number of days; number of cycles of 20 days; number of cycles of 360 days; number of cycles of 7,200 days; number of cycles of 144,000 days, and so on, completed since Creation Day.