Posts Tagged ‘Bolide’

Halloween Asteroid Warning

November 2, 2015

Many grim stories for children were devised to warn them of dangers. After all, children know mostly love at home, and if they did not read about evil, they would be unprepared.

The heavens just wrote a warning in the sky, and the children ought to be attention.

An asteroid passed within 480,000 kilometers of Earth on Halloween, October 31. That’s just a third more than the distance  of the Moon. Asteroids are (mostly) co-planar with Earth, As Earth’s diameter is 12,000 kilometers, an asteroid passing within a one million kilometer window centered on Earth has 1% probability to hit Earth. This 1% I brandish is much bigger than the low probabilities usually evoked by respected academics. (And a large planet, such as Earth, can function as an attractor. Also a hyperbolic comet barely missed Mars, last year)

So here we have a dangerous asteroid undetected until October 10. This puts a lie to the statistics on the probability of impact proclaimed in recent years.

Tunguska, 23 Years After The Explosion. 80 Million Trees Were Destroyed

Tunguska, 23 Years After The Explosion. 80 Million Trees Were Destroyed

The statistics brandished about the probability of impact are thus demonstrated to be fantasist: they depend upon craters found on the ground. However, most asteroids or comets will explode before reaching the ground (only iron meteorites have a high probability to pierce the atmosphere while keeping their integrity; comets are frozen rubble piles). As happened at Tunguska (see below). So one cannot infer from impact craters, the probability of bolides exploding in the atmosphere.

How big is the Halloween asteroid? Apparently 600 meters across. And it sneaked in the neighborhood, unforeseen, until 21 days before closest approach.

By comparison the Chelyabinsk meteor was a bit less than twenty meters across, with a mass of 13,000 tons.

This means the mass of Halloween asteroid was (13,000) x (30^3) = (13,000) x (27,000) ~ 300 x 10^6 tons, that is one third of a BILLION tons.

Moreover, it goes particularly fast.

Thus it contains at least 1,000 times the explosive power of the Tunguska Event.

How much is that? At least 1,000 times… 15 megatons. At least a million times Hiroshima.

I don’t believe an asteroid 10 kilometers across extinguished the dinosaurs (the Dekkan Traps did it). However, it certainly did not help them.

Tunguska was not small the forest destruction made a butterfly, 70 kilometers across, 55 kilometers long. The bolide penetrated the atmosphere at 7 am in June. Here is the testimony of S. Semenov, as recorded by Leonid Kulik‘s expedition in 1930:

“At breakfast time I was sitting by the house at Vanavara Trading Post [65 kilometres/40 miles south of the explosion], facing north. […] I suddenly saw that directly to the north, over Onkoul’s Tunguska Road, the sky split in two and fire appeared high and wide over the forest [as Semenov showed, about 50 degrees up—expedition note]. The split in the sky grew larger, and the entire northern side was covered with fire. At that moment I became so hot that I couldn’t bear it, as if my shirt was on fire; from the northern side, where the fire was, came strong heat. I wanted to tear off my shirt and throw it down, but then the sky shut closed, and a strong thump sounded, and I was thrown a few metres. I lost my senses for a moment, but then my wife ran out and led me to the house. After that such noise came, as if rocks were falling or cannons were firing, the earth shook, and when I was on the ground, I pressed my head down, fearing rocks would smash it. When the sky opened up, hot wind raced between the houses, like from cannons, which left traces in the ground like pathways, and it damaged some crops. Later we saw that many windows were shattered, and in the barn a part of the iron lock snapped.”

For the Halloween asteroid which just passed by, had it impacted Earth, the destruction would have roughly the same shape as Tungunska, an evil butterfly, but with ten times the dimensions.

Had the Halloween asteroid been aimed at Earth, could we have done a thing? Yes, nuke it. An Ariane V rocket could have been packed with a few 250 kilotons thermonuclear warheads (standard  in USA and France) and a supplementary thick casing of Uranium 238 (to boost the explosive power). The whole hellish device to be detonated by a quintupled proximity system, within meters of the asteroid’s surface.

A good asteroid and comet detection system would cost the price of a big Hollywood budget movies. It should be in the works. It’s not.

Ah, why Ariane V? Because there are always some of these highly dependable rockets ready for launch and it has plenty of spare impulse capability (second best would be the much lighter Soyuz, also always available). Of course the U.S. government could keep some heavy rocket at the ready (but I never heard of such a plan).

Conclusion? The western government with independent launch capability (France and the USA) ought to have a contingency plan for such a scenario, including the Uranium casing for a fission-fusion-fission device which could be assembled in hours, and ready to fit in a launcher such as Ariane V. So the technical details should be prepared. The Halloween asteroid proved we may not have much warning, in spite of all the boast to the contrary.

The Chelyabinsk meteor sneaked in, and would have sneaked in, even if it had been 600 meters across: it came from the Sun, The Sun’s direction, that is. This is the most probable impact direction (from own math). Don’t ask why there are two suns rising: we told you it could happen. It did happen in Brazil for a couple of events, one of them a triplet. In the 1930s.

But, of course, it will not happen: even certain catastrophe (the greenhouse melting) is addressed with a collective yawn.

One may wonder why this systematic bias towards unrealism, on the part of scientists themselves. Well they are just trying to please their masters, the politicians, who are themselves little more than employees of the fossil fuel industry (for reference, consider Gerhard Schroder, the Socialist German Chancellor, who became the head of a huge pipeline project with Russia; or the recently elected Strong Man of Canada, Trudeau, a boxer who is all for the Keystone Pipeline, and selling as much tar as he can).

The politicians themselves, and the political system they incarnate is well tolerated by the Public, because the Public itself is not interested by the Public Thing (Res Publica). Instead the Public is increasingly conditioned to prefer virtual reality.

Yesterday Donald Trump joked that he needed more global warming (it was cold outside where he was talking). Another example, closer to home: Yesterday’s essay of mine was hard, even venomous (in more ways than one). There were no comments, no “likes”.  My friend Paul Handover put up a dog pictures parade, and got a tremendous number of “likes”, much more of them than he gets in his own most thoughtful essays. This is, by itself, is a matter for thought. With the rise of virtual reality, and video games, we see an increasing rise of the mood that reality is something not worth bothering with…

As I pointed out yesterday, reality is a Black Mamba. It can stand up, and look in the eyes of human beings. And reality is aggressive: denial, far from helping, makes reality ever more vengeful.

At some point in the last 27 centuries of Roman law, it became obvious that, to be culprit, one needed a culprit mind (“mens rea”). Well, law should extend the culpability of minds ought to be extended to moods.

Patrice Ayme’

Nuke That Comet

October 2, 2014

Many are not held back about being strident. Why should not intellectuals do the same? After all, what they do is most important. So Nietzsche was strident, for example against German racist, anti-Semite, mediocre nationalistic, herd like aspiring bourgeois. Apparently that was not strident enough, and, somehow, the Nazis succeeded to make many believe that their worst enemy (Nietzsche) was their prophet.

The herd approves of those who are peaceful. So, to be taken seriously by the herd, to be a bovine intellectual, so to speak, one needs to be for peace, against conflict and anything violent. In particular, nuclear power, you know, from the nuclei which are all over matter, is not kosher.

Asteroid, 500 Kilotons, 17 Meters Across, 25 Miles Away.

Asteroid, 500 Kilotons, 17 Meters Across, 25 Miles Away.

The wall of a zinc plant in Chelyabinsk, Russia, was damaged by a shockwave from the meteor exploding 40 kilometers away, in 2013. With a mass of around 10,000 tons, 50% more than the Eiffel Tower, its explosion at 30 kilometers altitude damaged 7,200 buildings in 6 cities, injuring 1,500 people. Just a warning. It was the fiercest impact known since the Tunguska event… That destroyed 80 million trees in a radius of around 30 kilometers… Yet left not even a fleck of dust we know of. But there may have been others over the oceans, or even… Amazonia in the 1930s, where an object brighter than the sun impacted!

A 100 meters across asteroid would explode with around 100 Megatons of TNT energy, around double the largest nuclear device ever exploded (the notorious “Czar Bomba”; see the picture inside “The Worst)

For years would-be wise men, in scientist clothing claimed that nuclear weapons would not be efficient against asteroids. That was obviously an idiotic, and even dangerous position to have. in most plausible scenarios of a bolide impact, we would have little warning. A typical case is that of a comet on an hyperbolic trajectory, falling at enormous speed from the Oort Cloud.

Such bolides are attracted by planets like flies to honey. After all, gravitation is not called “universal attraction” for no good reason.

One such comets is going to graze Mars. It may as well have headed straight to Earth.

And then what?

Nukes. Big, fat, thermonuclear nukes.

Indeed, soft options then don’t work. Forget “gravity tractor” and “impactor.” The former involves using gravitational tug from a large spaceship to tweak an asteroid’s course. The impactor would crash at high speed into the asteroid to effect the same purpose… both may well fail, as asteroid are bizarrely constituted. Some are little more than rubble piles.

Soft methods would only work if the asteroid were small enough and seen soon enough. Many, as the one above, come from the Sun’s direction, so cannot be seen from Earth, as they catch up with her.

For large objects, short response times, or a comet, a nuclear explosion “is the only option,” (said, for asteroids, Bong Wie, a professor and director of Iowa State University’s Asteroid Deflection Research Center).

I wrote entire essays on this in the past. Now I am happy to announce that this point of view has been heard.

Some U.S. nuclear-warhead components, scheduled for disassembly, have gotten a new lease on life. Reason: possible use in defending the Earth against killer asteroids, or comets.

The National Nuclear Security Administration manages the U.S. atomic-weapons arsenal. The warhead components, containing highly enriched uranium, are being retained “pending a senior-level government evaluation of their use in planetary defense against earthbound asteroids,” an April 2014 report reveals. (A reason to keep components is that particularly powerful H bombs may have to be fabricated quickly, in the case of a looming large object, such as a comet; bombs in present arsenals can be delivered precisely, so are not very powerful, although they would be effective against very small asteroids.)

Asteroids with a diameter of about a kilometer or bigger, could “produce global devastation,” said the National Research Council in 2010. Hundreds cross Earth’s orbit, yet none are expected to impact for at least 100 years.

However at least 100,000 or more asteroids at least 50 meters in diameter cross Earth’s orbit. Probably no more than 5% of these “Near-Earth Objects” have been detected. A 50 meter asteroid exploding over a large city could kill up to 30 million people.

Those beasts tend to explode in the atmosphere, leaving no material remnants, as happened in Tunguska. So the statistics we have about how frequently they come knocking, are suspect.

It’s a world of forces, a violent world, out there. Better be ready.

When flying a civilization, we have to assume that, if it may happen, it will happen.  Especially if it’s very catastrophic. That’s the essence of Catastrophic Calculus, fundamental to flying planes, and civilizations.

Patrice Ayme’