Sunday, 1 January 2012

Armageddon 2012?

I was watching the film Armageddon with Bruce Willis a few days ago - as happens with these matters, it came to a freesat channel, doing the rounds, and I managed to record it. It is all about an asteroid hitting the earth, and mankind facing the prospect of mass extinction. That is, of course, quite a feasible scenario, although with NASA budget cut backs, the chances are slim indeed of any kind of drilling operation to split the asteroid asunder - even if it was possible to do this so that the pieces didn't hit the earth, as happens fortuitously in the film.

In fact, the film is in part about rough edged human beings, thrown into a wilderness to fend for themselves - the asteroid is a surrealist nightmare of craggy rocks, sharp and pointed light cathedral spires. Although the setting is space, the theme in part is the frontier spirit of America, the explorers trekking off into the outback and facing a sometimes hostile environment. I won't spoil the denouement, except to say that as expected, the project succeeds.

There's a token Russian for comedy effect from the Russian space station, and he has some of the best lines. Starting a jammed fuel line with a spanner, he says - Russian systems, American systems - all made with parts from Taiwan! And Paris gets wiped out - someone in the movies didn't like the French!

But the end of the world is often on the horizon in other ways. The Christian Harold Camping had predicted the end of the world, or at least the start of it, with the "rapture", a supposed moment when Christians are snatched away from an earth that will be dominated by the antichrist. This started with J.N. Derby, was very popular in the 1980s with Hal Lindsey's Late Great Planet Earth (the EU was the empire of the antichrist, the beast with many heads!) and continues to this day with the "Left behind" series of Tim LaHaye which presents it in a fictional form. It seems to be a peculiarly American phenomena, for while there are no doubt Christians in Britain and Jersey who believe it, it has never dominated the Christian mainstream, but remained resolutely on the margins, for fringe sects, and University student fundamentalism.

The New Age has its own take on the end of the world. According to a reading - actually a misreading - of the Mayan calendar, the end of the world will happen in 2012. Nonsense is also disseminated about the start of the Mayan calendar, which recent studies have pinned down not to tens of thousands of years BC, but to around  August 11, 3114 BC - based on archeological evidence from the date used on inscriptions, astronomical events recorded which tie in with the calendar in inscriptions, and historical documentary material (such as the Chronicle of Oxcutzkab). 4004 BC for the Usher Chronology of the Bible is actually earlier!

The "great cycle" of the calendar is 13 Baktuns, or 1,872,000 days, which neatly brings us to  December 20, 2012 but on a west panel at the Temple of Inscriptions in Palenque, a section of the text projects into the future to the 80th Calendar Round, which would be 13 October 4772. There is no evidence the Maya thought the world would end in 2012, but rather the contrary.

One significant matter is the length of years, just over 5,000 in a "great cycle", and I've heard it said in all seriousness that meant that the Mayans computed time in much vaster periods than other peoples. But a 5,000 year cycle is hardly large. Even 100,000 years, which would take us back to the Paleolithic, is barely something like 20 seconds to midnight on a clock which had all the age of the earth compressed to one 12 hour period. Or as another geologist said:

"Consider the Earth's history as the old measure of the English yard, the distance from the King's nose to the tip of his outstretched hand. One stroke of a nail file on his middle finger erases human history"

No ancient calendar came anywhere near estimates of the age of the earth. Eternalists like Aristotle thought it had no beginning, but the notion of deep time of an age of the earth of 4,540 000 000 years old was beyond them. If the Mayans had a calendar which could put the creation of the earth back then, I think their calendar would have a bit more credibility for 2012 end of the world.

And of the mass extinctions which have taken place - and there have been five significant ones - one was almost certainly set off by an asteroid impact on the earth around  65.5 million years ago, which led to the end of the dinosaurs. That remains the one real possibility, but I don't think it is that likely on the exact date of 20 December 2012.

What will happen after? Harold Camping has "recalibrated" his date, recalculating after he missed his date. I suspect strongly that the Mayan end of the world theorists will do the same!


Mark Forskitt said...

I cannot find a source for it, but I recall the Mayans had a notion that the earth/humans had several different creations and extinctions. The destruction have each been different including earthquakes, fires and the last one flood. The next should be of human origin apparently. Seems rather more probable than asteroid strike. Genetically engineered airborne contagion or breaching a tipping point in climate (eg massive methane release) would both my guesses for most likely this year. Hopefully we shall discover none of this happens.

Anonymous said...

How is Bruce these days?
happy new year!

TonyTheProf said...

Cyclical time seems to have been a Hindu concept, but that is linked to humans. The concept of the vastness of earth's history with no humans at all never occurred in any mythology.

There may be a human extinction, but that, of course, would be unlikely to kill off bacteria, and probably insects would survive quite well. The empire of the ant - as H.G. Wells, John Wyndham (Web)suggested.

Nick Palmer said...

Any asteroid computed to collide with Earth at some point can have its orbit "easily" diverted by landing a simple rocket on it that fires upwards. Even a micro percentage change in the asteroid's orbit would be enough to turn a direct hit possibility into a near miss.

TonyTheProf said...

Not so Nick, it depends on the momentum and mass of the asteroid. A single rocket might be as effective as sending off a firework from a moving boat, i.e., zilch.

Nick Palmer said...

Not so fast Prof. Think again.

Space, as Douglas Adams pointed out is incredibly big. The slightest push will have an effect on the orbit sufficient to do the job given the billions of orbital miles travelled by any object. No doubt you missed that I said "Any asteroid computed to collide with Earth at some point".

You were still stuck in the Armageddon scenario where they "suddenly" discovered a biggy heading right for us.

From Wiki article on Near Earth Asteroids:

"Near-Earth asteroids, or NEAs, are asteroids that have orbits that pass close to that of Earth. Asteroids that actually cross the Earth's orbital path are known as Earth-crossers. As of May 2010, 7,075 near-Earth asteroids are known and the number over one kilometre in diameter is estimated to be 500–1,000"

Asteroid 2889959%29_2002_NT7 is the main Armageddon like object known which until recently had been computed to have a low probability of hitting us in 2019 but recent work has shown that it will miss by around 38 million miles. Phew!

Its orbital period is about 2.3 years (link to a visualisation of the orbit)
and, eyeballing the orbit, it looks to have an orbital track of about a billion miles. They've been monitoring it since July 2002 so that would have given us around seven billion orbital miles to play with. To make it miss us by more than the Moon's distance we would have only needed to alter its course by around 0.0154 degrees. That's achievable with current rocketry, let alone Bruce Willis' atom bomb.

TonyTheProf said...

Observation: In March 1989, a 300 meter (975 foot) asteroid crossed the terrestrial orbit and missed the Earth by just six hours. Astronomers spotted the rock only when it was receding into space!

And NASA seems rather less optimistic:

NEO impacts are the only major natural hazard that we can effectively protect ourselves against, by deflecting (or destroying) the NEO before it hits the Earth. The first step in any program of planetary defense is to find the NEOs; we can't protect against something we don't know exists. We also need a long warning time, at least a decade, to send spacecraft to intercept the object and deflect it. Many defensive schemes have been studied in a preliminary way, but none in detail. In the absence of active defense, warning of the time and place of an impact would at least allow us to store food and supplies and to evacuate regions near ground zero where damage would be the greatest.

Nick Palmer said...

1989? They weren't really looking then - they did not set up LINEAR properly until 1996.

A 6 hours miss is about 430,000 miles or almost twice the distance of the Moon.

Anonymous said...

what would a rocket landed on an asteroid push against?

Nick Palmer said...

NASA actually seems to say more or less what I did...

Nick Palmer said...

Anon wrote:

"what would a rocket landed on an asteroid push against?"

Simples. Try looking up the physics of reaction motors