Debunking the “2012” Myth

On November 13, Sony Pictures International is releasing a new doomsday movie, “2012“. It’s about yet another end-of-the-world, Chicken Little “prediction” of the ancient Mayan Calendar (which the Mayans were not actually predicting). The movie will no doubt scare a lot of superstitious or uninformed people, and may even (grin) scare off sales of the Sony Playstation:

from the Sony website

I got wind of this in the November 2009 Sky and Telescope, the amateur astronomer’s magazine. There you’d find an excellent article in the newsprint magazine by E.C. Krupp, “The Great 2012 Scare”. Krupp wrote it as a primer to help us inform our more nervous friends that nothing of the kind is actually going to happen. Unfortunately the S&T article archives are down and unavailable for an extended “under construction” duration, so we can’t link this fine article for online viewing.

Krupp discusses the ancient Mayan Calendar (end of their religious calendar cycle 13 did not mean end of the world, even to them), planetary alignments, recent history of doomsday scares and a few basic facts about ecliptics and conjunctions. The 12-21-2012 fantasy event is supposed to revolve around the Mayan Calendar, planetary alignment, and alignment of the sun and Milky Way. Krupp concludes: “most of what’s claimed for 2012 relies on wishful thinking, wild pseudoscientific folly, ignorance of astronomy, and a level of paranoia worthy of Night of the Living Dead.”

And the problem’s not just this 2012 movie. Y2K was a bust, so now people into the occult, astrology, numerology, Nostradamus and the paranormal are all coming out of the woodwork. The movie is only feeding on the leftovers.

Common sense should tell us that if distant phenomenon like planetary alignment and the core of the Milky way could really buckle earth’s crust and slide us all into the ocean, then nearby objects of great mass, like new skyscrapers, could also topple nearby houses and seriously disrupt our infrastructures. Closer objects of negligible mass, like a sugar cube on the other side of my yard, should cause books to fall over in the living room bookcase.

Folks who haven’t really thought it through could still see a movie like “2012” and say, “there could be something to it.” Yet none of this ever happens in real life. Why? How can we prove it?

Astronomers, amateurs and anyone with a basic high school physics or astronomy course under their belt won’t need to read Krupp’s article, or this one, to grasp instantly that this scare is a bunch of bunkum. Folks in physics, astronomy and cosmology already have a good working feel for the numbers involved in planetary masses and distances, the scale of the solar system and Milky Way, and the fact that planetary alignments make for great photography but have utterly negligible effect on celestial mechanics.

How negligible?

Cosmic catastrophe rumors are as irritating as kudzu weed and seeping sewer lines, so I decided to crunch some numbers on a spreadsheet and find out for myself.

The 2012 movie premise rests on a couple of related fallacies about celestial alignments or “conjunctions”. We need to look at them for a minute. First, it is frightenly common for people to buy into the false notion that an alignment of two or more planets exerts some kind of significant tidal or other unfavorable influence on Earth. Second, some idiot threw in a corollary that alignment of the sun with the Milky Way would have an additive negative effect.

We’re already in the Milky Way, for crying out loud – our Sun is in our galaxy’s Orion Arm. Even the producers of the movie admit this item is hyped. The core of the Milky Way is so vast and nebulous that any time frame of an Earth-Sun-Galactic Core “alignment” would be measured in hundreds of years, not some specific day. We are going to throw that one out right away.

Tidal Forces

Any cosmic gravitational disruption that caused continental plates to buckle and slide into the sea would be a tidal action. There are actually several components to tidal forces, or Tides:

  1. The static force of gravitational attraction between two bodies, such as the Moon and Earth’s oceans.
  2. The dynamic rate of change of those forces. The Earth’s daily rotation about its axis controls the frequency of low and high tides, hence, their rate of change.
  3. Differential forces acting on Earth: “Even though the Sun is 391 times as far away from the Earth as the Moon, its force on the Earth is about 175 times as large. Yet its tidal effect is smaller than that of the Moon because tides are caused by the difference in gravity field across the Earth.” – see footnote 1.

Gravitational force or attraction between two masses is proportional to the multiplied product of those two masses, but it’s inversely proportional to the square of the distance between them. The effect of the Sun on Earth tidal cycles is about 3% of the effect of the moon, despite the Sun’s enormously greater mass, because the sun is so far away that there is negligible difference in the solar gravitational pull on Earth’s two sides.

Earth’s tides are diurnal (roughly twice a day) and of course we take tidal periodicity for granted. But, if the moon were instead locked in geosynchronous orbit, the “moon side” of the earth would always have a permanent “high tide”, and the antipodal point on the opposite side would always have a low tide. Similar effects on the earth’s crust, even if much larger, would also be constant, so there would be no “event”, and no sudden, cosmically-induced “buckling” of the Pacific Plate, for example.

The Sun’s rotation about the Milky Way takes about 225 million years, so (1) Earth has already been around the circuit more than 15 times, and it’s still here. (2) if the galactic core did exert any kind of non-negligible force on earth’s mantle (it doesn’t), the pull would be static and constant over millions of years. Nothing about that is going to change in 2012.

Random Planetary Alignments

Krupp’s magazine article had a nice illustration to show that, for Friday December 21, 2012, there’s not even going to be any planetary “alignment”. The distribution of the 8 planets about their orbits will be pretty random. The two largest planets Saturn and Jupiter will be on opposite sides of the solar system from us. Inner planets Venus and Mercury will be on the other side of the sun from Earth. You might get a nice picture of them in the same evening sky, right around sunset, if you have a good wide-angle lens. That’s the only reason why astronomers get excited about planetary conjunctions.

Mass and Gravitational Attraction

The Sun has about 1000 times the mass of Jupiter, and Jupiter has about 1000 times the mass of the Earth. For our purposes here, a rough rule of thumb has been that all of the planets combined have “just over” a thousandth the mass of the sun.

I did my spreadsheet to calculate gravitational attraction between Earth and selected objects in the solar system. Below I compare the gravitational effect of those bodies on the entire mass of the Earth with the Moon’s effect. I chose the Moon because we can all relate to its effects on the tides.

The formula for gravitational attraction (for discussion of units and calculation see Wikipedia, footnote 3) is used in my calculations:

F = G \frac{m_1 m_2}{r^2}

Note that the force of attraction is calculated in my spreadsheet between entire planetary bodies. The formula can be used for any two masses at distance r. The resultant forces are expressed in Newtons, but we are really only interested in the ratio compared to the effect of the Moon.

Summary of results:

objects mutual attraction (Newtons) ratio (compared to moon)
Moon-Earth
1.99261E+20
1.000
Jupiter-Earth
1.91903E+18
0.0096307
Saturn-Earth
2.30904E+16
0.00011588
Mars-Earth
4.18667E+16
0.00021011
Venus-Earth
1.13602E+18
0.00570115
SUN-Earth
3.55313E+22
178.3151853

After completing my spreadsheet I found the useful web page Tides, referenced in footnote 1. The author presents similar comparisons in pounds exerted against the mass of one human body. I happen to weigh about 160 pounds. Jupiter’s closest approach, the author reported, would pull on my weight by about 0.0000056 pounds (footnote 1). Nice.

Solar System - not to scale - startswithabang.com

 

Conclusions:

  • Even mighty Jupiter exerts less than 1% of the Moon’s gravitational force on Earth, because of its great distance
  • If Jupiter, Saturn and Mars were all aligned in conjunction with the Earth, the total attractive force would be additive, and the sum (0.00995669 of Moon’s influence) would still be miniscule.
  • We can throw out the incalculably small effect of the galactic core. Its distance to the sun is about 26,000 light years. If the Milky Way were scaled to a diameter of 10 meters, our solar system would be about 0.1mm (half the size of a dust mite), and we are located inside the Milky Way.
  • Following the link in footnote 1, we find a detailed explanation of why the sun’s influence on Earth tides is only 3% of the moon’s. The key here is distance: the distance from the moon to the near side of Earth is appreciably less than its distance to Earth’s far side.”The side nearest to the second body experiences a greater force, while the opposite side experiences a lesser force.” – Wikipedia footnote 4.
  • Apart from the Sun and Moon, none of the aforementioned celestial bodies can or do induce any noticeable action whatsoever upon Earth, its tides, or geological plate movements.

We’re not going to go through tidal calculations (far side/near side) because only the Moon is a key player here, and actual tidal forces are much more complex. Our own high school math calculations demonstrate that we can easily repeat published work of professionals in the field. All of this is more than sufficient to conclusively confirm that the outer planets could not possibly influence terrestrial tides or crustal upheavals.

Night of the Living Dead. Indeed! Many people enjoy watching those old B movies just for the comic value of really lame plots, weak cinematography, and bogus acting. Unfortunately, this time they’ll not get the hysterical shrieks of a Shelley “Titanic” Winters. Count on other histrionics, though. “2012” is destined to claim its rightful place in the genre.

©Alex Forbes October 4, 2009

 

References


1. Tides; “Jupiter Effect” – Relative weights; Sun’s tidal effects, “Jupiter” scare; why the moon is the dominant tidal influence. More. A HyperPhysics classroom project. The author is Rod Nave.

2. Planetary Fact Sheet – Metric – NASA. Raw distance and mass data; other useful stats.

3. Newton’s law of universal gravitation – Wikipedia. Calculation of forces involved and units of measurement.

4. Tidal force – Wikipedia. Differential tidal forces on near and far side of close planetary bodies. See also footnote 1.

5. Spreadsheet calculating gravitational forces exerted on Earth by Moon, Sun and several inner and outer planetary bodies. By Alex Forbes.

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6 thoughts on “Debunking the “2012” Myth

  1. What would the effects of gravitational lensing from the sun have? Focusing low energy cosmic or other unknown from the core of the Milky Way.
    Would the earth be within this concentrated part of this lensing at this time?
    Would the larger plants be behind the sun increasing the effect?
    Would we be now moving into this region, if there was one?
    More auroras, heating of atmosphere, with more particle interaction with our electromagnetic field.
    Would this extra interaction be the cause of the spike in global warming lately not just being man made? (Which I agree 100% is contributing to it)

    The opposite could be true if we were pointing away from the Milky Way core, excessive cooling, Ice age. What was it 13000 years ago? 1/2 cycle?
    I am no physic’s guy, nor any science guy, And I figure that some smart Mayans figured out a starting point of a great timing cycle (good for them), and that cycle of time will end/begin again, that’s all it means to me a time piece. Nothing to do with doomsday end of the world, but after watch lots of shows on Nostradamus and the Mayans and the explanations given which to me had no real meat to it or good explanations or solid reasoning, nobody brought up the possibility of gravitational lensing as a possibility!
    I am not saying that we will be at the focal point or that it’s the end of the world far from it but sure would like to know were it is, if there is one.
    If we are within that area the implications of the interaction of this concentrated particles and energy would be something to think about. Would it not?
    Pat

  2. Hi Pat, thanks for writing your comments. Under the circumstances, yours are interesting questions that should also be addressed. I hadn’t read that gravitational lensing was being associated with the current threat-to-earth speculation. Happily I can assure you: while gravitational lensing is a very real and wonderful phenomenon for astronomers and astrophysicists, it has virtually zero potential impact for our geological and biological environment. No threat whatsoever, actually or even potentially.

    As most of us have read, lensing is simply the bending of light waves by very massive objects at enormously vast distances. “Very massive” means something on the scale of a large galaxy, or black hole, or a large galaxy with a large black hole at its core. Our sun is way to small (by orders of magnitude) to create any measurable gravitational lensing, but even if it did, this would only be useful to alien astronomers some billions of light years distant from us.

    Vast distance is the other key, then. Our neighboring “sister galaxy” Andromeda is massive enough to be a candidate for gravitational lensing, but the light rays do not bend THAT much – we are “only” 2.5 million light years away from it. Objects that do display lensing properties at a distance are normally not visible at “local neighborhood” distances.

    There’s a useful lay article in Wikipedia if you want more detail without getting bogged down in a science lecture: http://en.wikipedia.org/wiki/Gravitational_lensing

    So we are really talking about the curvature of space-time in deep gravity wells. That lets out the sun and any neighboring objects. The energy intensity of anything deflected by lensing is very, very small, since the focal distance is so great: images that only Hubble and the giant telescopes can pick up.

    Even gamma rays at these distances are so faint and diffuse as to pose no threat. Now, supernova gamma ray bursts in focused parallel jets could be a more credible but remote concern, but this is a totally different and more concentrated effect. From what we know of our local galactic neighborhood, there are only a few supernova candidates in this category that might go off sometime in the next billion years or so. Those jets are so tightly beamed that it is like having a laser pointer tag you when it is dropped randomly on the other side of the country!

    You might also download and read the Sky & Telescope PDF catastrophe primer by editor Robert Naeye. I posted that link to the PDF yesterday, in this Astronomy department. The download is free and available to anyone. Cheers!

  3. Excerpt from wiki

    ‘According to general relativity, mass “warps” space-time to create gravitational fields and therefore bend light as a result. This theory was confirmed in 1919 during a solar eclipse, when Arthur Eddington observed the light from stars passing close to the sun was slightly bent, so that stars appeared slightly out of position.’

    Now take a whole galaxy of stars. Milky Way. The visible light and the rest of spectrum of electromagnetic waves and a pinch of unknown?, bending slightly just enough to concentrate.
    Add that to the suns output and maybe a degree or 2 intensity increase.
    This might account for the warmer than usual or colder than usual years, depending on were the earth is lined up in relation to the sun and the denser part of Milky Way.
    If this statement was true ( this I do not know), then an alignment would intensify this as the sun passes directly in front of the mass of the denser part of the Milky Way, 2012 (-/+ 3 years) and we would see an increase in temperature caused by the interaction of particles/electromag. radiation or unknown?, Likewise a cooling when the opposite happens.

    Just a thought from a layman.
    PS: Thanks for the links, and taking the time to reply.

  4. Hi Pat, the effects of Milky Way core are thoroughly discussed in the Sky & Telescope links. And of course we are already in the Milky Way, and it can’t act as a gravitational lens of itself. As far as lensing of the combined energies of whole other galaxies, think about the math for a minute. Energy intensity drops off with the square of the distance. We don’t need a pencil and paper to see that the reciprocal (inverse) of a million light years’ distance, squared, is about as close to zero as you can get.

    Sure, Earth has well-known heating and cooling cycles and these are being hotly discussed around the world for other reasons – climate change and atmospheric pollution. The 11-year sunspot cycle, the Maunder Minimum effect, and precession of Earth’s axis all account for changes on a scale of 2 or 4 degrees. But the “alignment” ideas aren’t looking realistically at the math. Not only is there no evidence any kind of celestial alignment has ever influenced earth’s climate, when you look at the math of how that would work (I did in my own article), you can see there’s just no way it could be a measurable factor on either direct heating/cooling, or upon ionization of the upper atmosphere.

  5. At the end of the day or whenever, believe what you like… Pat, feel free to worry, prepare, do what makes you feel practical. However remember this, “…worrying is like being on a rocking chair; sure it passes the time but it doesn’t get you anywhere!…”

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