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The sky is falling!

The cosmos put on quite a show yesterday, sending two massive asteroids (one a total surprise) Earth's way within hours of each other.

A good thing, all in all. Nobody died, but the astronomic coincidence -- and especially the stunning dash-cam images out of Chelyabinsk -- focused a lot of minds on a real threat our civilization faces.

First reports were that the meteor breakup released about 10 kilotons of energy, less than either the Hiroshima or Nagasaki blasts, at a height of perhaps 30 kilometres or more. Just powerful enough to scare governments out of their complacency. Reports later in the day, however, were enough to scare me too:

The meteor didn't weigh 10 metric tons, but 7,000. It exploded much closer to the ground than first thought, and with force comparable to many modern nukes. If it had been mostly iron and nickel rather than rock, and/or contacted the atmosphere at a far steeper angle, Chelyabinsk and its million-plus people might have been destroyed. Yesterday!

This is being described as a once-in-a-century event, Tunguska being the other bookend. But for about half that length of time, mutual assured destruction was the military philosophy of the two superpowers. We came close to blundering our way to annihilation during the Cuban missile crisis. Now it turns out we also ran a real chance of a random natural event triggering our death wish.

It isn't getting better. The superpowers today may be a bit less quick on the draw, but imagine a similar meteor hit in North Korea, Israel, anywhere in India or Pakistan. Would military minds wait for scientists to weigh in before rushing to "retaliate?" Maybe, but millions could die instead.

It has always been in our long-term interest to develop the technology to detect and track Earth-grazing asteroids of all sizes, and learn to deflect them if they pose a deadly threat. Now that we've seen how closely they can mimic our own nuclear warheads, we have an even more pressing reason, no?

No worries, mate...Bill Nye (the science guy) assures us that the informal monitoring effort currently directed at making sure that we always miss our rendezvous with annihilation by at least the 15 minute margin most recently separating us from that really, really big-ass asteroid has mapped (wait for it) fully one in one hundred similar stones.  Hmm.  Excuse me, I think I need a new planet--I'll get back to you in a bit...

NASA has wanted for years to develop tracking system with the capability to spot small asteroids. Right now they can only pick up larger ones then the one the other day. The one that whizzed by us was only found a couple of months ago by an astronomer. We need a lot more lead in time then we have now to try to destroy or change course of it before it hits earth. But we have too many fools in our government that don't see any purpose of scientific spending because there is no short term monitary profit for the capitalist also too many flat earth Bible believers.

Could you explain this comment  

also too many flat earth Bible believers

From my readings of the Bible, it says he is going to make a NEW Earth.

I believe an asteroid could transform our present one, into a new one. 

If the planets current coverage of 3/4 water, overwhelms the planet; things would definitely be New.

The money for the research of large asteroids, should be used to relocate people away from the coastal areas.

Then again where do we move to?

I just hope one of those massive asteroids doesn't hit Yellowstone Park or Mnt. Rainer or we'll be dodging magma flows and that would surely make things New.

The Pope has fallen and there are signs in the Heavens; hmmmm  Maybe I need a life insurance policy.  wink

Canadians to the rescue yet again:

Considering that it's said to be such an improvement over existing detection systems, this telescope is amazingly small. Its lens or mirror (I'm not sure which it has) is just 15 cm (six inches), comparable to many backyard telescopes.

Thanks for the read. The picture of the little satellite is interesting. I wonder how long something that small can stay in orbit until it needs replaced. They didn't say anything about it's life span only it is a night and day 24 hour operation. I know NASA has been wanting to map all the asteroid belts deep in space. This is going to keep a eye on closer stuff and all the junk we have dumped up there. But it is still a great achievement because it don't take a large rocket to launch it.

Yesterday was very exciting even though NASA went to great lengths to downplay how closely we dodged these bullets.  I want to ask someone if there is any way to calculate what would have happened if the two asteroids coming from opposite directions had collided.  My math, physics and just general information about trajectories, mass etc. are not up to the task.  No doubt someone is already working on that and I will just have to wait.



 I want to ask someone if there is any way to calculate what would have happened if the two asteroids coming from opposite directions had collided.

Calculate the cost of the panic, if the information was available?

Like the movie line in Jaws "We need a bigger boat" 

People will be asking "You got bigger magazine clips"?

Given their relatively tiny size, the chance of two asteroids colliding is infinitesimal. Even if they did, they'd just release their combined energy into space, leaving us earthlings with two less threats to worry about. No, the problem is that Earth poses such a big, juicy target.

For sure the little one would have been annihilated by the collision but not so sure about the big one.  And what are the odds of two completely unrelated asteroids showing up the same day, eh?  

I did wonder if maybe the opposite directions was a result of the little one getting caught by earth's gravity and slung around.   Could they have been companions before that, the little one scouting for the big one. ;) Twitter was all abuzz wondering who or what may crawl out of that lake in Siberia.

Guess I will just have to keep reading. What a chore :D


  A pinprick compared to the Tunguska explosion, but still scary. But I take comfort in knowing that no meteorite larger than a baseball has ever hit a city.

Thought this from David Brin today might interest you.

Professor William Napier and Dr. Janaki Wickramasinghe have completed computer simulations of our sun’s movements in its outer spiral location in the Milky Way, and determined that we are now entering a danger zone where molecular clouds might perturb the solar system -- the odds of asteroid impact on Earth go up by a factor of ten

Your actual quote is from Dick Pelletier's blog, which I give little credence to. The rocks that hit or graze Earth come from our solar system's asteroid belt. Is he suggesting that every 37 million years or so, the system passes through molecular clouds that will knock 10 times as many asteroids out of their orbits? Those clouds are not stationary things we collide with; they revolve around the galactic center at basically the same speed as our sun does. I have trouble seeing how a gradual thickening of the interstellar medium is going to have such a whopping gravitational effect. The second threat he cites is even less credible, at least to me.

I have no idea who Dick Pelletier is.  The quote is copy/pasted from David Brin's blog post at Contrary Brin.   He is an astrophysicist who writes hard science fiction.  The post I linked to began by mentioning that he would be participating as an advisor at the Spring meeting of NASA's NIAC: New and Innovative Advance Concepts.  He has also appeared on BBC twice recently to answer questions about the Russian meteorite.  I have no idea how seriously he credits Napier and Janaki's work but at least enough to pass it along as an FYI item.  I followed suit thinking you might be interested.


I did find it interesting; I just disagreed with it.

But here's where it gets confusing: If I click on the words David Brin in your comment, I don't find the quote you cite. If instead I click on the phrase inside the boxed quote itself, "entering a danger zone where molecular clouds might perturb the solar system," that takes me to Pelletier's blog, where it appears as the third paragraph. And Pelletier, like me, doesn't appear to be an astrophysicist.

This is, I think, the relevant abstract from Monthly Notices of the Royal Astronomical Society. The people who did the research are real astro folks. This doesn't mean they're right, or even marginally sane on this one point. I found this when I was looking to see if any scientific response had been posted (i.e., by some other qualified person). Haven't found one yet.

Thanks.  That is really way above my level of comprehension but what little of it I did understand did not seem so unreasonable, assuming reasonableness as a measure of sanity.  I mean, the oort cloud itself is only hypothetical.  It has never been observed directly and it is not really so much a cloud as a debris field anyway.  Why is it unreasonable to suppose that if and when our paths cross that the possibility of impacts would increase?  

From my perspective it is just another idea that will be seized on by the OMG! WAGD!* rush seekers and good for a few books and couple of movies of the same genre.  Maybe one of them will combine it with Yellowstone erupting since the time cycles look to line up. ;D

Look at it this way: science often needs sciency stuff to keep people interested.


*oh, my god! we're all gonna die!


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