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When Comets Attack
Red Flayer writes "Popular Mechanics is running a story that describes one of the more interesting explanations for the Tunguska explosion of 1908: 'Now, a controversial new scientific study suggests that a chunk of a comet caused the 5-10 megaton fireball, bouncing off the atmosphere and back into orbit around the sun. The scientists have even identified a candidate Tunguska object — now more than 100 million miles away — that will pass close to Earth again in 2045.' Note that Popular Mechanics' definition of 'close to' is somewhat different than most people's — the comet will be 3.8 million miles away at its closest. At any rate, the key to this theory is that hydrogen and oxygen in the ice shard exploded upon entering the atmosphere, resulting in the difficult-to-explain blast pattern (previous theories contend that the object must have 'skipped' on the atmosphere and then re-entered at the exact same spot). This would also, sadly, dash the theory that Nikola Tesla was responsible."
This artist's rendition of the explosion graced the back cover of this month's The Planetary Report (from The Planetary Society). It illustrates how the bolide likely blew up above the ground and hence produced no crater. The artist is Don Davis.
One simple rule for its versus it's
I think this is one of the great what-ifs of recent history... what if this event took place in a populated area, rather than in the Siberian woodlands? We still don't know what happened today, so how would people have dealt cognitively with it back in 1908 if thousands or even millions had died?
I find it intriguing to consider.
Do what thou wilt shall be the whole of the Law
all these comet theories are great, but how to they explain the extra Carbon 14 found in tree rings in that area, for that year? (The trees that hadn't been blown down, of course.)
Source: Encyclopedia Britannica
It was shown back in 1966 that the butterfly shape of the fallen trees may be caused by the several explosions combined with the ballistic wave.
The Russian researchers built a model of the site (1:10000), with explosion modeled by an explosive cord with an explosive charge at the end. The forest model was built from the tiny flexible wires with plastic crowns.
They have shown that placing the cord at some inclination angle (close to 30 degrees) the impact shape was clearly resembling the butterfly shape of Tunguska event.
The abstract (in Russian) is here:
http://tunguska.tsc.ru/ru/science/conf/1966/zotkin/
The FA talks about the comet having a 'host planet' around which it orbited long enough for the 'host planet's' magnetic field to electrolyse the water in the comet into hydrogen and oxygen. It was the ignition of the hydrogen that is claimed to have causes the explosion. Possible of course but it seems a bit of a stretch to me. Occam's razor and all.
Of course, every sentence says "citation needed" after it
Actually, its pretty accurate. Japan was hurting economically before the war even began. The USA stopped selling Japan raw materials, like steel and oil were cut off, and in response the Japanese extended the imperial drive into the resource rich pacific.
But even then you have to keep in mind that the industrial japan of world war II was nowhere near the industrial japan of today. The GDP of Japan was a fraction of that of the USA and to some extent the Japanese Navy headed into 1941 was built up over the years by accumulating a bunch of different classes of warships. On the other hand the USA of then was not the USA of today. Back in those days the USA was a protectionist industrial powerhouse, rather than a free trading banking state.
A great web site maps out the economic disparity between the two:
http://www.combinedfleet.com/economic.htm
Some things are just amazing... like, just look at how many Essex class aircraft carriers, aircraft, and battleships the USA built. Everyone raves about the Japanese 70,000 ton Yamato, but there are some Navy fans out there that say the USS Iowa class could probably come out ahead in that fight, there were four of those versus two Yamatos.. and, if it had been a battleship war, and the Iowa couldn't do it, then the Montana would.
But as it was it was a carrier war. We build 25 Essex Class carriers, the Japanese a fraction of that. We build more than 300,000 aircraft, the Japanese a fraction of that. We have radar. The Japanese don't. We have self sealing fuel tanks. The Japanese don't.
The Japanese had no shot to win that war.
This is my sig.
Does anyone recall the the interviews done of the people in the area after the blast.
There was a reporter/documentarian that went over there and talked to the locals.
They talked about a metallic cavern 150 miles away from tunguska that was persistently radioactive.
The older guys talked about it shooting plasma balls into the sky after they noticed it charging up for a month. And they noticed this because it would kill off more stuff around it.
Mainly, it looked like a defense grid that had the nasty side effect of irradiating everything within 20-80 meters. All the wildlife and grass around it died- and the people apparently did the first couple times as well.
I can't remember what reporter documented this though. Do any of you older guys recall seeing this maybe 15 years ago? It was an ancient defense grid that was basically a radioactive capacitor(magma sourced?) that vaporized incoming asteroids. It's ok if you don't. Just thought I'd throw that out there, since considering other physical impossibilities apparently is.