Russian Meteor

A Russian city about 900 miles from Moscow had a bus size meteorite blow up over it, injuring 1,100 people.

A similar explosion of a 100 ft. diameter meteorite leveled millions of trees in Tunguska back in 1908. Tunkguska is about 1,200 miles from the recent one.

What's up with Siberia and big meteorites? Why there?

Quote: Ayecarumba

A similar explosion of a 100 ft. diameter meteorite leveled millions of trees in Tunguska back in 1908. Tunkguska is about 1,200 miles from the recent one.

No one really knows for sure what hit Tunguska. There's some controversy about whether even there is a crater. If there sin't one, it wasn't a meteor. Other hypotheses suggest a comet, a meteor or comet braking up over the are rather than hitting it, and more exotic thngs such as a quantum black hole or a loose bit of anti-matter.

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What's up with Siberia and big meteorites? Why there?

There's a lot of Siberia available.

Considering the shock-vave area of the Tunguska, that event was rated in Mega-tonnes. This one today in the kilotonnes range 6-7.

Tunguska event probably an ice ball with compacted stone and metal... verrry efficient blast. Todays looks like Metal-alloy dense and small and had a high degree of disintegration lowering the yield substantially.

Quote: Nareed

There's a lot of Siberia available.

Logical, but I'm starting to wonder anyway. Of course, events over the ocean are unlikely to ever be in the stats, so that's another thing.

Quote: Ayecarumba

What's up with Siberia and big meteorites? Why there?

This meteor is now being estimated at 10,000 tons releasing 300 to nearly 500 kilotons of energy.
Four years ago an 80 tonne meteor hit Africa and the Sudan. It was detected before impact. It does seem strange that the much larger Siberian meteor was not detected.

As Nareed pointed out, Siberia is pretty big, so it might be just coincidence. of two large impacts in just over one century.

One wonders if one of these meteors could start a tsunami?

Quote: Pacomartin

One wonders if one of these meteors could start a tsunami?

I don't think it's big or fast enough. Yes, the 300 kt figure is impressive, but the atmosphere sucks a lot of energy from rocks of that size. And when they break up, if they do, the individual fragments are too small.

Now, I'm not one to panic or overestimate threats. But I think it's high time NASA, ESA, an whatever the Russian and Chinese call their space agencies, to get together and seriously plan a system to 1) detect near Earth asteroids and 2) work out the means to divert them.

The Russian meteor was, in the overall scheme of things, very very minor. But later the same day a much bigger rock passed under 30,000 km from the Earth's surface. That's a near miss. If that asteroid had hit, we would all be huddling for warmth and out hunting for food. And if it hit on the ocean (and there's a lot more ocean than land in this planet we call home), many coastal areas would have been wiped out. Not destroyed. Wiped out. The tsunami produced by such an impact, would make the 06 Asian tsunami look like nothing much.

Oh, any dependable system for deflecting large asteroids would perforce include posting some small nuclear weapons in orbit. Get used to it. There is no way around it, and it's not at all dangerous if some sensible precautions are taken (such as disarming the nuke if it enters the atmosphere).

Quote: Nareed

Oh, any dependable system for deflecting large asteroids would perforce include posting some small nuclear weapons in orbit. Get used to it. There is no way around it, and it's not at all dangerous if some sensible precautions are taken (such as disarming the nuke if it enters the atmosphere).

I would assume that we would know about this asteroid weeks or months in advance (not hours). I am not sure why putting the nukes in orbit would gain much advantage over a ground based system.

Asteroid 2012 DA14 passed 27,520 km above the planet traveling at 13 km per second. One would hope that the next time an event like this occurs we will be able to test a device to deviate it's path slightly.

Quote: Pacomartin

I would assume that we would know about this asteroid weeks or months in advance (not hours).

I wouldn't. You must make allowances for emergencies and the unexpected.

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I am not sure why putting the nukes in orbit would gain much advantage over a ground based system.

Read above. then read below:

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Asteroid 2012 DA14 passed 27,520 km above the planet traveling at 13 km per second. One would hope that the next time an event like this occurs we will be able to test a device to deviate it's path slightly.

Travel in space is more about speed than distance. Both Earth and any given asteroid orbit the Sun at different average speeds. The way to catch up to an asteroid is to match it's speed relative to the Sun. It doesn't matter if it's one mile away or a billion miles away. And once you match speeds, assuming you aimed in the right direction and omitting many other details, you'll stay near that asteroid until you or it change speeds.

Now, suppose an asteroid is heading to Earth and will collide. Given enough time, you can catch up to it and use any number of means to alter its path. Not given enough time, you must perforce abandon a rendezvous and try something different, like detonating a nuke near the asteroid to alter its path.

If you had hours, possibly it's all too late anyway. It depends on many factors. But if you had a few days, then an orbiting nuke with plenty of fuel for a variety of trajectories is just what you need. Launching from the ground you'd need: 1) a massive rocket, say like an Enrgiya or a Falcon 9, 2) reasonably good weather at the launch site, 3) an adequate launch window, etc. It's also easier, and faster, to move an orbiting satellite to a new attitude than to ship a ground based nuke to a new location because the one you picked offers no good path to the asteroid, say if you required a polar trajectory.

Of course you'd have may ground facilities, not just one. Then you need to provide security, technicians, maintenance (and rockets are still temperamental at launch time), services, etc, etc.

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Above 1,000 km, orbital debris will normally continue circling the Earth for a century or more.

http://orbitaldebris.jsc.nasa.gov/faqs.html

I was wondering if we could get something up in orbit, it would stay available.

Quote: Pacomartin

This meteor is now being estimated at 10,000 tons releasing 300 to nearly 500 kilotons of energy.
Four years ago an 80 tonne meteor hit Africa and the Sudan. It was detected before impact. It does seem strange that the much larger Siberian meteor was not detected.

As Nareed pointed out, Siberia is pretty big, so it might be just coincidence. of two large impacts in just over one century.

One wonders if one of these meteors could start a tsunami?

Yes they could start one. Eventually one will hit and do real damage. Then he earth will shake off humans like the irritating fleas we are and some new life form will be in top.