Hmm...I just came across this article that seriously addresses the small but real possibility of asteroid impact.

Perhaps we need to be a bit more pro-active. Here's a snip from this paper:

" Finally, we believe that international human society (and elements of it, like the U.S. government) needs to make an informed, formal judgement about the seriousness of the impact hazard and the degree to which resources should be spent toward taking steps to address, and plan for mitigation of, potential cosmic impacts. The existing unbalanced, haphazard responses to the impact hazard represent an implicit judgement; but that judgement does not responsibly address the extraordinary and unusual consequences to nations, or even civilization, that could result from leaving this hazard unaddressed in such an arbitrary, off-hand way. For example, we believe it is appropriate, in the United States, that the National Research Council develop a technical assessment of the impact hazard that could serve as a basis for developing a broader consensus among the public, policy officials, and governmental agencies about how to proceed. The dinosaurs could not evaluate and mitigate the natural forces that exterminated them, but human beings have the intelligence to do so."

Perhaps it won't happen during our lifetime and the statistical risk is small but I can't help but think some sort of planning would still be a real good idea.

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An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

What did you have in mind? And BTW, this isn't ATM. It's more like General Astronomy. 8)

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"The oxen are slow, but the earth is patient."

Well, I don't have anything in mind...the authors of the paper however, do have quite a few ideas:

"Research, planning, and preparation need to commence now, although it remains to be determined how far such activities should go, given the low probabilities of having to address any real, major impacts in our lifetimes. We believe that several issues need to be addressed in the near future.



l The notification system (concerning a predicted potential impact) needs to be cleaned up, expanded, and officially adopted and implemented.



l Official clearinghouse/s for the best information need do be developed (potential nuclei for such functions, including fledgling web sites or analogous capabilities, already exist at Jet Propulsion Laboratory, NOAA, Spaceguard Foundation, and the IAU Minor Planet Center, among others).



l Serious connections need to be developed with the hazard mitigation community, including agencies like FEMA.



l More objective approaches to communications need to be developed to minimize misunder*standing of this hazard, which is so mismatched to our personal experience base (extreme rarity or low chances of happening vs. extreme potential consequences). In other words, the Torino Impact Hazard Scale needs to be further developed, extended, distributed, and explained.



l Official international channels for exchanging information about NEO hazard-related issues and events need to be developed.



l Within the United States, an interagency approach, and assignment of responsibilities, for dealing with the NEO hazard needs to be developed; the Global Change Program may provide a template. Analogous steps need to be developed in other nations and to coordinate among nations.



l Education about the NEO hazard would be facilitated by conducting a high-visibility, international conference on the NEO hazard, emphasizing the non-astronomical, non-NEO-deflection issues that have so far been treated as backwater concerns in previous NEO hazard conferences. Perhaps a newsletter should be instituted.



l Given widespread interest in extending the Spaceguard search down to bodies much smaller than the 1 km goal of the U.S. search efforts, a thorough evaluation of ground- vs space-based approaches needs to be made. Although spacebased efforts are usually vastly more expensive, they have advantages that may balance the costs in some cases; in other cases, the cost of spacebased efforts may not be relevant (e.g. the searches may be piggy-backed onto other endeavors that pay most of the costs).



l We consider the case of comets to be astonishingly intractable (they are difficult to detect, there is a short time between detection and impact so the object can't be studied carefully, a comet may be difficult or time-consuming to get to so it may not be possible to "blast" it until it is almost here, a comet's motion is difficult to predict, and the structural nature of comets is poorly known -- they break-up independently and unpredictably). So we recommend more detailed study of the nature of comets and of cometary detection/mitigation strategies. At a minimum, we must quickly assess how large a part of the impact hazard comets are.



l Chemical rockets may have quite wide applicability to deflection scenarios; we recommend more study of that technology.



l In certain cases of attempted mitigation, disruption is more likely than deflection. More research needs to be done in this area, including studies of the potential consequences of disruption.



l All of these recommendations are predicated on a political decision about the importance of the NEO hazard and about the level-of-effort that should be expended in addressing it. The technical community needs to identify potential criteria (beyond simple comparisons of death rates from various hazards) for making this judgement. We recommend that official, objective study/ies by bodies like the National Research Council be done for this purpose. Ultimately, society's decision about how seriously to address the impact hazard will have to involve broad segments of the public, beyond the technical community."


Also, to my knowledge this sort of thought (ie, planning for an asteroid impact) is rather "against the mainstream" as it's not really presently an accepted notion. If the BA wants to move it...that's fine too.

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An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

How about a hand full of morphine tablets and a bottle of great scotch?
Or if you find yourself a survivor, get over it and get on with what is left over.

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It's not what you know or don't know, but what you know that isn't so that will hurt you. Will Rogers
http://www.craterchains.com/ns/nspage.html

Well, there was a time in Europe when the "black death"(plague) was an accepted fact of life. With the advance of germ theory and modern medicine what was once unavoidable is now a non issue. If we apply ourselves perhaps there's a solution to this eventual problem as well.

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An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

now there's a good suggestion... make that two bottles of great scotch: a 30 year old Bowmore and a 25 year old The Macallen and i will skip the morphine.

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Who are you going to believe, me or your own eyes? -- Groucho Marx

I say support the effort, be one of the searchers if it interests you, but don't forget the rest of the hazards in the world while you are at it. I'm still terribly bothered every time I think of Gene Shoemaker being killed in a vehicle collision when he was so concentrating on asteroid collisions.

http://www2.jpl.nasa.gov/sl9/news81.html

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I would do a nuclear test on an asteroid in space to see how it affects them. By the way, are nuclear tests in space safe?

i reckon that the aditional radiation will hardly matter...

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Who are you going to believe, me or your own eyes? -- Groucho Marx

I was on the SHIELD team in '99 (ref'ed in the article). If something like that ever moves forward, the capabilities exist already to handle a lot of threats. On the back of the envelope, landing an engine as small as NEAR Shoemaker's on a few km diameter asteroid, with enough lead time (~20 years) can divert a potential impactor's orbit enough. The untested bits of tech are precise landing and grappling on an irregular body, but NEAR showed we could get close even with a spacecraft not designed to land. Also you'd need to get quite a bit more fuel up there than NEAR had by the end, but SEP might be part of that solution.

The bigger problem is the smaller bodies with shorter warning times - the kind that can wipe out states instead of continents. There are many more of them, and we certainly haven't found all of them. An additional problem we'll never be able to completely control is the long period comets slinging around the sun once every several hundred or thousand years. There aren't many of them, but we won't get a lot of warning if one has our name on it.

Another good ref: Hazards Due to Comets and Asteroids (1994)
by Tom Gehrels, Mildred Shapley Matthews, A. M. Schumann

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“The simplest schoolboy is now familiar with truths for which Archimedes would have sacrificed his life.” – Earnest Renan

Wow! Now just how cool is that! I'm quite impressed.

Regarding the smaller bodies with the shorter warning times, are there any thoughts about how that threat could be handled?

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An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

It would have been more impressive if the project had gotten farther. Maybe it will at some point - if not SHIELD then its children or cousins through other agencies. As far as I can tell, they're still trying to figure out if planetary protection is really NASA's business or the militiary's.

Well, That's were Kinetic energy and/or nukes might be the only way. The question of realtive energy is whether the appropriate metaphor is shooting bb's at rolling snooker balls or shooting bullets (even explosive ones) at a runaway semi.

There can come a point where you have to decide whether concentrating the impactor's energy in a single spot is better or worse than distributing it across a wide area of the planet. If you can't make some of it miss altogether, you might just want the earth to absorb more of the kinetic energy in one spot, rather than dumping more into the atmosphere. Part of the Bad Science of the Deep Impact (movie) scenario was that all those little pieces of the big comet that burned up in the atmosphere wouldn't sum to a harmless light show (if indeed all the chunks could have been made small enough). They'd heat the place up.

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“The simplest schoolboy is now familiar with truths for which Archimedes would have sacrificed his life.” – Earnest Renan

But...the problem with this analogy is that the Black Plague was, as you said, an "accepted fact of life", while on the other hand, civilization-destroying asteroid impacts (unless I missed the memo) so far have not been.

We applied ourselves to solving the ongoing human problem of "disease", but so far there is no ongoing human problem of "asteroid impacts so large as to require FEMA's mobilization". There's just an "eventual problem", the same way there's an "eventual problem", I suppose, with "overexploitation of mineral resources on Mars".

Absolutely, but I'll bet the dinosaurs weren't too happy when that asteroid hit the Yucatan. It's just a matter of time until something does hit us and cause some major damage. As for it being a priority, I guess not. Personally, I worry more about Al Quada but all it would take would be one asteroid on the right, err...wrong heading to really ruin your day.

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An open mind is like an open window...without a good screen you'll get all sorts of weird bugs!

Unfortunately, I think we need an asteroid impact very soon. It will teach humanity that there's no point in terrorism, no point in unneccessary violence. Many people may die, but the strength we gain after overcoming the impact will prove very useful to our future, I think.

I personally don't believe an asteroid will ever hit Earth again. I can't explain it in scientific terms, but piecing together everything I have ever read on this subject leads me to believe it just ain't gonna happen. Sure, there will always be NEO's to give the perception that such an event could take place.

I do believe the ever increasing temperatures on Earth will exceed what humans are capable for sustaining life. Therefore, we will eventually die off. Unless, we explore space to find a more suitable way to survive.

I don't believe the high temperatures are anything that can be reversed. My theory is that as the galaxy expands, the planet's are getting closer to the Sun. Hence, the reason why the temperatures rise. Is this to far fetched, or could I be on to something?

Hehe Candy, I believe just the same you do (that probably never again will an asteroid hit earth) - but for totally different reasons :wink: : With a probability as high as 1 minus the probability that a big asteroid will hit us within 100 years, I believe we will never be hit again, because I think within the next 100 years, we will have found methods to avoid such a catastrophe.
Maybe a "moderate" impact of a house-sized body on valuable property might speed up funding for research...
But I should be careful what I wish for :roll:
As for the planets getting closer to the sun - why should they, and what has this to do with an expanding galaxy?
The only effect that influences earth's orbit I know of is that the sun slowly loses mass which will make earth recede farther from the sun - slowly, settling down at approx. 1.8 AU by the time the sun reaches the red giant stage.

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Mars Society.

I could live with that, unless it is my house! =D>
The AU's will never change. That is set in stone. [edited to add I did not factor in your 1.8 AU - just going on lay woman observations] Try to visualize what I mean. The planet's position in our Solar system will change. They will eventually be closer to the Sun.

Or, everyone could fight for the remaining resources and the world could fall into total chaos and anarchy. 8-[

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For example,

Sun..........Planet..........[Galaxy's End

Sun..........Planet............................... .........[Galaxy's New Ending

Scientifically, won't the Planet be closer to the Sun (if you base it on the galaxy's new end)? To me, the closer the planet is to the Sun (from the end of the galaxy), the higher the temperature will get. #-o

[edit to add additional thought]

Hi Candy, I got your PM, I came as soon as I could.

Now, why is the galaxy expanding? What is that about?

Now you reply, 8 minutes before I have to leave for work. Yeah, my vacation starts in 9 hours! The BABB will have my full attention, then.

I thought our galaxy was gobbling up the surrounding galaxy's. :-k Am I using the wrong terminology?

Oh... I don't think people need something as tangible ad scarce resources to start a fight. It seems that religion, moral codes, and cultures provide more than enough reasons to galvanize some people to fight to the death....
&lt;sigh>

The Magellanic Clouds are fairly close but not that close, but the Saggitarius Dwarf galaxy is being torn up--it's on the other side of the Milky Way from us though. About a hundred million years until we turn around there, if it hasn't moved by then.

The Magellanic clouds are embedded in a long dust trail (the Magellanic stream) that contains them like pearls on a string, so there is some gravitational interaction with our Milky Way; the clouds lose gas to it, and our Galaxy probably prevented at least the LMC from developing a spiral structure similar to M33, while the "clouds" warp the disc of our galaxy ever so slightly. Elliptical galaxies seem to be less vulnerable it seems, since the two companions of M31 are, or so it looks, not affected by the big neighbor - less gas, and no disk to warp

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Mars Society.