Asteroid Impact Preparedness

[witgenestone]

7 kps? I thought 20 kps was the most likely velocity. But would it matter ?

 

[yevaud]

Yeah, up around 17 kps. I missed the "1" when I was typing it.<br /><br />(Moggy fragging keyboard. Gotta clean the thing) <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[green_meklar]

<blockquote><font class="small">In reply to:</font><hr /><p>I have to ask what happens to the dyno gel after it has done its job?<p><hr /></p></p></blockquote><br />As far as I know it's not toxic to wildlife and fairly biodegradable, so you don't really have to worry about it.<br /><br />Besides, we dump who knows how many tonnes of garbage and pesticides and fire retardant all over the surface of the Earth every day, so even if the dyno-gel <i>was</i> harmful to the environment, the damage it would do wouldn't be very significant and would be enormously outweighed by the benefits of stopping a hurricane.<br /><blockquote><font class="small">In reply to:</font><hr /><p>Only 100 times its own mass in water?<p><hr /></p></p></blockquote><br />It's a round figure, I could be off by quite a bit. Besides, the idea isn't to get rid of all the clouds but merely to disrupt the air currents and cool down the ocean surface. And also, keep in mind that it doesn't have to absorb every bit of the water that falls as rain; just absorbing a small fraction of it could be enough to get the rain going. <div class="Discussion_UserSignature"> <p>________________</p><p>Repent! Repent! The technological singularity is coming!</p> </div>

 

[MeteorWayne]

Just stop drooling on it <img src="/images/icons/smile.gif" /><br /><br />The minimum speed for an asteroid of substantial size (so that you can neglect the atmosphere slowing it down) is 11 km/sec. That's strictly from the earth's gravity.<br />Most meteorite producing events impact the atmosphere between 17 and ~ 40 kps due to the fact that they revolve around the sun the same direction as we do.<br /><br />Real danger comes from comets as well, since while smaller and lighter, they can hit the atmosphere at up to 74 kps (~ 40 miles per second) if approaching in the opposite direction,such as Tempel-Tuttle, Swift-Tuttle, and Halley. These are the parent objects of the Leonid, Perseid, and for Halley's comet, the Orionid (coming up in october) and eta Aquarid meteor showers.<br /><br />Meteor Wayne <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[yevaud]

<blockquote><font class="small">In reply to:</font><hr /><p>Just stop drooling on it<br /> <img src="/images/icons/laugh.gif" /><p><hr /></p></p></blockquote><br /><br /><img src="/images/icons/tongue.gif" /><br /><br />You know you have housecleaning to do, when you upend your keyboard, hit it, and dust comes falling out...<br /><br />(Being as it's my keyboard, I'd think all dust would catch on fire and disintegrate...) <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[MeteorWayne]

The other scary part is... what does mother nature do with all that energy that doesn't get redistributed by the hurricanes. They are part of the energy balancing process of the ocean-atmosphere system. If you take out that method that moves that huge amount of energy, where does it go?<br /><br />The answer is, we don't know. Is that an experiment we want to run? <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[MeteorWayne]

Well not much dust came out of mine<br />{whack, whack}<br /><br />But what the heck is all that other stuff????? <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[yevaud]

(With apologies to Hercule' Poirot)<br /><br />Little Gray Cells. <div class="Discussion_UserSignature"> <p><em>Differential Diagnosis:  </em>"<strong><em>I am both amused and annoyed that you think I should be less stubborn than you are</em></strong>."<br /> </p> </div>

 

[MeteorWayne]

If they weren't mine, I would have known that! <img src="/images/icons/smile.gif" /> <div class="Discussion_UserSignature"> <p><font color="#000080"><em><font color="#000000">But the Krell forgot one thing John. Monsters. Monsters from the Id.</font></em> </font></p><p><font color="#000080">I really, really, really, really miss the "first unread post" function</font><font color="#000080"> </font></p> </div>

 

[willpittenger]

That's what I asked earlier. Nature abhors a vacuum. <div class="Discussion_UserSignature"> <hr style="margin-top:0.5em;margin-bottom:0.5em" />Will Pittenger<hr style="margin-top:0.5em;margin-bottom:0.5em" />Add this user box to your Wikipedia User Page to show your support for the SDC forums: <div style="margin-left:1em">{{User:Will Pittenger/User Boxes/Space.com Account}}</div> </div>

 

[search]

I think we have to reconsider the 10Km asteroids size...1km is bad enough...<br /><br />Here is an excelent site Spaceguard Survey:<br /><br />NASA Asteroid and Comet Impact Hazard:<br /><br />What is a NEO?<br /><br />Near-Earth-Objects (NEOs) are small objects in the solar system (asteroids and short-period comets) with orbits that regularly bring them close to the Earth and which, therefore, are capable someday of striking our planet. Sometimes the term NEO is also used loosely to include all comets (not just short-period ones) that cross the Earth's orbit. Those NEOs with orbits that actually intersect the Earth's orbit are called Earth-Crossing-Objects (ECOs).<br /><br />What size NEOs are dangerous?<br /><br />The Earth's atmosphere protects us from most NEOs smaller than a modest office building (40 m diameter, or impact energy of about 3 megatons). From this size up to about 1 km diameter, an impacting NEO can do tremendous damage on a local scale. Above an energy of a million megatons (diameter about 2 km), an impact will produce severe environmental damage on a global scale. The probable consequence would be an "impact winter" with loss of crops worldwide and subsequent starvation and disease. Still larger impacts can cause mass extinctions, like the one that ended the age of the dinosaurs 65 million years ago (15 km diameter and about 100 million megatons).<br /><br />The threshold for an impact that causes widespread global mortality <br />and threatens civilization almost certainly lies between about 0.5 and <br />5 km diameter, perhaps near 2 km. Impacts of objects this large occur <br />from one to several times per million years.<br /><br />Approximately 2,000 near-Earth objects (NEOs) larger than one km diameter revolve around the sun on short-period orbits that can occasionally intersect the orb

 

[witgenestone]

You guessed right. Thanks for the info.

 

[witgenestone]

What I meant was that humanity has good chance for survival if a one mile asteroid hits. It would probably kill of a lot of us in a cold (or hot) shower, and disrupt our technological advances accordingly to size,speed, angle, density etc. Nice tsunamis up to a height of 1 km?? To completely destroy civilization it is estimated that an asteroid has to be around 10 km. I got this info directly from nasa/jpl.<br /><br />1 km asteroid is more than bad enough. But a 1,5 km is bader. and so on.<br /><br />What worries me most about the smaller ones is that if one hits (and maybe in the wrong place) it can disrupt the technological advances so much that we wont get enough time to develop technology to protect against a new and maybe larger one incoming. The probability of an ELE asteroid impact is very small, but smaller bodies hits more often.<br /><br />How long does the average american live? Here again we see probabillity compared to a lifetime. The problem is that an average norwegian lives longer <img src="/images/icons/smile.gif" />. 1/1000 is a good bet. But most people wouldnt bet all their money. This is anyways guesswork according to Yevaud.<br /><br />Let's say it was 1/x probability for a large impact to occur the next 100 years. And it consisted x planets with the same conditions as the earth has, with intellegent life. I would assume this if an asteroid comes in for a crash landing on our planet. Then it would be comforting to know that probably they at least they didn't get it. I mean, they didnt win the lottery.<br /><br />In the event of an ELE: We have been dead for a very long time, and only lived for a brief one. Death must be more familiar to us. But since we all fear it that much, it must be hell. <br /><br />And thanks for the new links.<br /><br />edit: some critical errors corrected

 

[search]

It is all about money and priorities.<br /><br />If a NEO />1km would appear out of blue (or black) I am sure something would be done. If <1km it would depend where. Until no NEO shows is face Spaceguard and retoric because there is a lot of "fronts" to tackle.<br /><br />There is always space for humour...

 

[witgenestone]

Probably, but I got no concept of money or of priorities <img src="/images/icons/wink.gif" />.<br /><br />I sure hope there is space for humour here. At least in our local group.

 

[witgenestone]

from http://www.nearearthobjects.co.uk/report/annexB.htm<br />: 1992, Oct 9 Peekskill, New York (car hit). <br />Now what's the probability of that happening??<br /><br />It was btw a 2 meteorite building hits here in norway in august 2006 (of the same body).

 

[witgenestone]

Regarding no neos showing up and rhetoric:<br />then we should hope that a little neo comes by for a vistit first? A little one maybe, about 100 m in diameter? It is likely.

 

[witgenestone]

SEARCH.<br />In a post above you wrote the following: <br />"Approximately 2,000 near-Earth objects (NEOs) larger than one km diameter revolve around the sun on short-period orbits that can occasionally intersect the orbit of the Earth. Only about 7% of this estimated population has been discovered......"<br /><br />Where did you get this information? And when was it written. We have discovered a lot more NEO's the last few years:<br />http://neo.jpl.nasa.gov/stats/<br /><br />And regarding large neo's from:<br />http://impact.arc.nasa.gov/intro_faq.cfm<br />"As of the end of 2004, astronomers had discovered more than two thirds of the larger Near Earth Asteroids (diameter greater than 1 km). None of the known asteroids is a threat, but we have no way of predicting the next impact from an unknown object."

 

[search]

Its from the site I provided under NASA link in that post. You need to search further in the site or just follow link below:<br /><br />http://impact.arc.nasa.gov/gov_nasastudies.cfm<br /><br />You are correct. The information is from 1995 so much more as been done since then.