This is interesting. I saw photographs of the Tunguska event and if you look at the way the trees were felled and the blast radius it is easy to assume (if you did not take note of the date of the occurence and the fact no one had anything close to atomic bombs then) that is was a nuclear explosion. The photography showed in essence a similar blast pattern that a nuke would have caused. Actually if my memory serves me correctly for many years some people said it was an 'explosion as anti-matter from space collided with matter' since few believed back then it was caused by a meteorite! (I always chuckle over the anti-matter explanation though ......anti-protons and positive electrons have only been created in extremely controlled scenarios hence a 'mass' of anti-matter impacting Earth is a little ludicrous).
Anyways this whole Asteroid/Meteorite thing is a greater threat than most people think since over 90% of the space surrounding Earth is not scrutinized at all. And most big chunks (like the one that passed close to Earth a couple of months ago) are discovered when it is feasibly too late!
Imagine what would have happened had a Tunguska-type space rock impacted Boston during the height of the Cold war, or if a ferrite meteorite had exploded 1 mile above Moscow, USSR in 1981! I am almost certain that the fallout would have been a nuclear strike (and the Red Line phone connection between Moscow and Washington would not have helped if such an event occured). After think how close the world came to nuclear conflagration during the late seventies and eighties due to silly stuff like cloud formation accumulations over Alaska (and a couple of years ago Russian subs went into threat alert when a metereological rocket launched by Norway was not reported to all the military echelons and was misinterpreted as an SLBM Trident launch from a US submarine. Reports say that a nuclear launch count-down had begun and was only stopped with a minute left, just like the movies! And the sad thing is Norway had reported they would launch the rocket months in advance, but that notice did not reach everyone).
And, switching sides, there is this Russian Rocket Soldier who worked for the Soviet Rocket Forces Department who still receives cards and thank you letters from grateful people since he single handedly stopped a nuclear war. Their radar had picked up some anomaly (i guess the usual cloud formation) and the Ruskies had prepared for a launch. It is only this guy who disobeyed orders and managed to stall the launch for enough minutes for additional info to come through and prove it was not ICBMs over Alaska but something else. The order had already been given to launch.
I saw some info that the US also made several such mistakes as well. It seems God must have seriously been watching over Earth because according to probability a nuclear war should have broken out during the cold war. But nothing happened!
Now imagine if a meteorite aerial burst over New Delhi or Mumbai in India or Karachi or Islamabad in Pakistan occured! I can bet serious cash that depending on the spot volatility between the two nations (which by the way is always high) there would be a launch between the two nations.
I read somewhere that 10 million dollars would be enough to ensure that all the space is looked at ....yet no one has agreed to cough up the funds. I may be wrong, but 10 million dollars is nothing for government, and if it would give prior warning on a meteorite strike (even if after the warning there is little we can do to stop it .....without heading into silly science fiction) it would at least ensure silly Arabs and jittery Hindus with nuclear weapons will not act stupidly thinking the other is employing a first strike!
If 10 million bucks can at least lessen the chances of that i think it is a good investment. I do not understand what is so hard in getting 10 million bucks for this ....it is one of the things i do not comprehend!
And at the same time, billions are being spent on the Space Station for little return (see related thread in Front Page News).