Re: [Vo]:Near earth asteroid info
In reply to David Roberson's message of Wed, 13 Feb 2013 16:45:19 -0500 (EST): Hi, [snip] A blast years in advance might spread the material in both time and space sufficiently to protect us. You have to be a little careful here. If it's too far in advance, and the blast doesn't accelerate the pieces beyond their own escape velocity, then the gravitational pull between them might bring the thing back together again before impact. It may require a bit of math to get the timing just right. BTW I don't think the water would be necessary. At the temperature of a nuclear blast, a high temperature plasma forms, surrounded by a gas. I think the plasma and the gas would provide enough pressure. However it might require a Tsar Bomba to do the job. BTW2 Asteroids that are rubble collections would obviously be better candidates than completely solid bodies, but unfortunately we don't have any say in the matter. ;) Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
RE: [Vo]:Near earth asteroid info
Is this an overlooked possibility... ? A few meteorites/asteroids are composed of nickel-iron-cobalt and are essentially large ferromagnets. None has reached our surface as a strong permanent magnet AFAIK (unless that part of the Excalibur myth). Even if one became permanently magnetized on its journey through space, it would exceed its Curie temp on contact with Earth's atmosphere and lose most of its polarization ... so it is unlikely that the magnetic field of earth would play much of role in altering any near miss orbit of a megaton magnet. But what about the extreme situation of a nickel iron cobalt meteorite with a few rare earth elements - becoming strongly polarized like the best permanent magnet - and also picking up a coating of ice in the Oort cloud to protect it from exceeding its Curie point for several minutes, so that it was attracted to one of Earth's poles. Unlikely, of course ... but is it out of the realm of possibility?
Re: [Vo]:Near earth asteroid info
It would be unfortunate if the blast merely delayed the reconstruction of the asteroid, but I suspect that this would be unlikely. The escape velocity of an asteroid is very low if I recall, which is due to the relatively small mass of the object. Isn't it normally assumed that the asteroids are just small fragments of a much larger body that was destroyed by collisions between large planet like precursors? My thought about water arose because the underground testing of nuclear blasts tends to look wimpish. This seems to be the result of the fact that a nuclear weapon has a relatively small amount of mass that does not carry away much momentum. The energy is enormous, but the momentum effects are minor in comparison. The water vaporizes quickly and generates a lot of pressure to act upon the plug of matter above, kind of like a large gun. I am not confident that the vaporization of normal asteroid material would generate sufficient push without a little help. The underground test containment seems to suggest the lack of extra push from standard rock based materials. Dave -Original Message- From: mixent mix...@bigpond.com To: vortex-l vortex-l@eskimo.com Sent: Thu, Feb 14, 2013 5:39 pm Subject: Re: [Vo]:Near earth asteroid info In reply to David Roberson's message of Wed, 13 Feb 2013 16:45:19 -0500 (EST): Hi, [snip] A blast years in advance might spread the material in both time and space sufficiently to protect us. You have to be a little careful here. If it's too far in advance, and the blast doesn't accelerate the pieces beyond their own escape velocity, then the gravitational pull between them might bring the thing back together again before impact. It may require a bit of math to get the timing just right. BTW I don't think the water would be necessary. At the temperature of a nuclear blast, a high temperature plasma forms, surrounded by a gas. I think the plasma and the gas would provide enough pressure. However it might require a Tsar Bomba to do the job. BTW2 Asteroids that are rubble collections would obviously be better candidates than completely solid bodies, but unfortunately we don't have any say in the matter. ;) Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
In reply to David Roberson's message of Sun, 10 Feb 2013 22:10:12 -0500 (EST): Hi, [snip] I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I wonder if anyone has modeled the difference between the two scenarios? Dave ..as I hinted at in my previous post, an explosion in space would not only result in a spatial spread of the debris, but also a temporal spread. By way of a weak analogy consider the difference between a single kilo of high explosive detonated in a crowded place and a hurricane. The high explosive may well kill more people than the hurricane, yet the hurricane has vastly more energy. Of course, the degree of spread obtained would increase the longer the time of the explosion in space was before the time of impact. (gives the pieces more time to spread out). Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
Now I understand what you were suggesting. If the impact time of the pieces was spread out over a very long time frame, then it would probably work. I initially thought that you were just thinking of one big blast close to Earth that tears the large asteroid into many smaller meteorites. A blast years in advance might spread the material in both time and space sufficiently to protect us. I am curious about the magnitude of a explosion that could blow one of these into bits. The underground nuclear test blasts seem to generate a tiny external effect, which I suspect is due to the small momentum associated with a nuclear weapon. The energy release is immense, but the force is modest when contained within a chamber. That is why I was thinking of adding a large quantity of water adjacent to the weapon that would be converted into high pressure steam which would then send an expelled asteroid chunk on its way. I would prefer to see the asteroid diverted by some process that left it intact if at all possible so that it would entirely miss the planet. The next best alternative as far as I know would be to blast a modest chunk of the material at right angles to the path with enough momentum to achieve the same goal. The smaller ejected material should be thrown hard enough to pass mostly on the other side of the Earth from the now diverted main body. Some debris would no doubt still impact the Earth, but it would be a grand light show. Dave -Original Message- From: mixent mix...@bigpond.com To: vortex-l vortex-l@eskimo.com Sent: Wed, Feb 13, 2013 1:28 pm Subject: Re: [Vo]:Near earth asteroid info In reply to David Roberson's message of Sun, 10 Feb 2013 22:10:12 -0500 (EST): Hi, [snip] I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I wonder if anyone has modeled the difference between the two scenarios? Dave ..as I hinted at in my previous post, an explosion in space would not only result in a spatial spread of the debris, but also a temporal spread. By way of a weak analogy consider the difference between a single kilo of high explosive detonated in a crowded place and a hurricane. The high explosive may well kill more people than the hurricane, yet the hurricane has vastly more energy. Of course, the degree of spread obtained would increase the longer the time of the explosion in space was before the time of impact. (gives the pieces more time to spread out). Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
Guys,
Just a thought experiment I had since we are near a solar maxima.
If the average CME is a billion tons and three per day occur on
average somewhere on the surface during maxima, moving between 30 and 3000
miles/second, how come we are not struck by Mt Everest (est. weight a
billion tons as a cone) more often? Where is all that stuff going?
On Saturday, February 9, 2013, David Roberson wrote:
This would be true if the pieces came down over a large area and at a
moderate number per hour. I suspect that a large mass of individual pieces
coming down close together would behave a lot like one big one. The energy
contained within the large mass of individual meteorites would be about the
same as that in one.
Dave
-Original Message-
From: mixent mix...@bigpond.com javascript:_e({}, 'cvml',
'mix...@bigpond.com');
To: vortex-l vortex-l@eskimo.com javascript:_e({}, 'cvml',
'vortex-l@eskimo.com');
Sent: Sat, Feb 9, 2013 10:51 pm
Subject: Re: [Vo]:Near earth asteroid info
In reply to de Bivort Lawrence's message of Thu, 7 Feb 2013 23:28:29 -0500:
Hi,
Wouldn't blowing up an asteroid merely create a lot of smaller pieces raining
down on earth, with only a few deflected into non-collision paths.
If the pieces are small enough, they will burn up in the atmosphere
harmlessly.
[snip]
Regards,
Robin van Spaandonk
http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
I think you need to take into account that the Earth is a very tiny target at our distance from the sun. Perhaps you should calculate roughly how much of that CME actually impacts us per unit of surface area. Since it begins as a plasma, it most likely is not dense enough to cause much trouble. Dave -Original Message- From: ChemE Stewart cheme...@gmail.com To: vortex-l vortex-l@eskimo.com Sent: Sun, Feb 10, 2013 7:51 am Subject: Re: [Vo]:Near earth asteroid info Guys, Just a thought experiment I had since we are near a solar maxima. If the average CME is a billion tons and three per day occur on average somewhere on the surface during maxima, moving between 30 and 3000 miles/second, how come we are not struck by Mt Everest (est. weight a billion tons as a cone) more often? Where is all that stuff going? On Saturday, February 9, 2013, David Roberson wrote: This would be true if the pieces came down over a large area and at a moderate number per hour. I suspect that a large mass of individual pieces coming down close together would behave a lot like one big one. The energy contained within the large mass of individual meteorites would be about the same as that in one. Dave -Original Message- From: mixent mix...@bigpond.com To: vortex-l vortex-l@eskimo.com Sent: Sat, Feb 9, 2013 10:51 pm Subject: Re: [Vo]:Near earth asteroid info In reply to de Bivort Lawrence's message of Thu, 7 Feb 2013 23:28:29 -0500: Hi, Wouldn't blowing up an asteroid merely create a lot of smaller pieces raining down on earth, with only a few deflected into non-collision paths. If the pieces are small enough, they will burn up in the atmosphere harmlessly. [snip] Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
On Sun, Feb 10, 2013 at 7:51 AM, ChemE Stewart cheme...@gmail.com wrote: Guys, Just a thought experiment I had since we are near a solar maxima. If the average CME is a billion tons and three per day occur on average somewhere on the surface during maxima, moving between 30 and 3000 miles/second, how come we are not struck by Mt Everest (est. weight a billion tons as a cone) more often? Where is all that stuff going? Because the earth represents about 1.4 x 10^-11% of the sphere (read target) at our orbital radius?
Re: [Vo]:Near earth asteroid info
We are a tiny target but we do have a gravity field and solar wind connecting us that should make us appear a little mo Bigga? Stewart Darkmattersalot.com On Sunday, February 10, 2013, Terry Blanton wrote: On Sun, Feb 10, 2013 at 7:51 AM, ChemE Stewart cheme...@gmail.comjavascript:; wrote: Guys, Just a thought experiment I had since we are near a solar maxima. If the average CME is a billion tons and three per day occur on average somewhere on the surface during maxima, moving between 30 and 3000 miles/second, how come we are not struck by Mt Everest (est. weight a billion tons as a cone) more often? Where is all that stuff going? Because the earth represents about 1.4 x 10^-11% of the sphere (read target) at our orbital radius?
Re: [Vo]:Near earth asteroid info
That bullet is moving pretty fast in our direction. Gravity might not have much of an opportunity to work very well on it. This would be a good one for you to model. Dave -Original Message- From: ChemE Stewart cheme...@gmail.com To: vortex-l vortex-l@eskimo.com Sent: Sun, Feb 10, 2013 11:54 am Subject: Re: [Vo]:Near earth asteroid info We are a tiny target but we do have a gravity field and solar wind connecting us that should make us appear a little mo Bigga? Stewart Darkmattersalot.com On Sunday, February 10, 2013, Terry Blanton wrote: On Sun, Feb 10, 2013 at 7:51 AM, ChemE Stewart cheme...@gmail.com wrote: Guys, Just a thought experiment I had since we are near a solar maxima. If the average CME is a billion tons and three per day occur on average somewhere on the surface during maxima, moving between 30 and 3000 miles/second, how come we are not struck by Mt Everest (est. weight a billion tons as a cone) more often? Where is all that stuff going? Because the earth represents about 1.4 x 10^-11% of the sphere (read target) at our orbital radius?
Re: [Vo]:Near earth asteroid info
Ok, let,s say billions of tons per day is missing us, some near, some far,
how come the inner solar sytem, over millions of years is not littered with
millions of Mount Everest chunks and sub chunks of debris everywhere? I
would think that itty bitty asteroid would be small potatoes...
On Sunday, February 10, 2013, David Roberson wrote:
That bullet is moving pretty fast in our direction. Gravity might not
have much of an opportunity to work very well on it. This would be a good
one for you to model.
Dave
-Original Message-
From: ChemE Stewart cheme...@gmail.com javascript:_e({}, 'cvml',
'cheme...@gmail.com');
To: vortex-l vortex-l@eskimo.com javascript:_e({}, 'cvml',
'vortex-l@eskimo.com');
Sent: Sun, Feb 10, 2013 11:54 am
Subject: Re: [Vo]:Near earth asteroid info
We are a tiny target but we do have a gravity field and solar wind
connecting us that should make us appear a little mo Bigga?
Stewart
Darkmattersalot.com
On Sunday, February 10, 2013, Terry Blanton wrote:
On Sun, Feb 10, 2013 at 7:51 AM, ChemE Stewart cheme...@gmail.com
wrote:
Guys,
Just a thought experiment I had since we are near a solar maxima.
If the average CME is a billion tons and three per day occur on average
somewhere on the surface during maxima, moving between 30 and 3000
miles/second, how come we are not struck by Mt Everest (est. weight a
billion tons as a cone) more often? Where is all that stuff going?
Because the earth represents about 1.4 x 10^-11% of the sphere (read
target) at our orbital radius?
Re: [Vo]:Near earth asteroid info
On Feb 10, 2013, at 9:03, ChemE Stewart cheme...@gmail.com wrote: how come the inner solar sytem, over millions of years is not littered with millions of Mount Everest chunks and sub chunks of debris everywhere? The reference to Mt Everest is perhaps a little misleading. Better would be Mt Everest vaporized in a kiln and now in a diffuse, plasma state. Eric
Re: [Vo]:Near earth asteroid info
The 1859 carrington event was followed by 1860, the year of meteors, is that the kind of diffuse plasma you are referring too? On Sunday, February 10, 2013, Eric Walker wrote: On Feb 10, 2013, at 9:03, ChemE Stewart cheme...@gmail.com javascript:; wrote: how come the inner solar sytem, over millions of years is not littered with millions of Mount Everest chunks and sub chunks of debris everywhere? The reference to Mt Everest is perhaps a little misleading. Better would be Mt Everest vaporized in a kiln and now in a diffuse, plasma state. Eric
Re: [Vo]:Near earth asteroid info
In reply to David Roberson's message of Sun, 10 Feb 2013 11:45:07 -0500 (EST): Hi, [snip] I think you need to take into account that the Earth is a very tiny target at our distance from the sun. Perhaps you should calculate roughly how much of that CME actually impacts us per unit of surface area. Since it begins as a plasma, it most likely is not dense enough to cause much trouble. Dave This is also the answer to you own previous post. ;) When the pieces are small, the ratio of surface area to volume is much greater than for a single large meteor. That means vastly more friction, and consequently more heat absorbed by the mass of rock, sooner. IOW they vaporize in the upper atmosphere long before they get near the ground. The added friction has another effect too. It tends to spread them out over a larger area. Nevertheless, I imagine it would quite a light show, and the shock wave might still be somewhat dangerous. Furthermore, blowing the thing up while still in space will also spread the pieces over a much larger area by the time they hit the atmosphere, and some of them may either never hit, or not until a following orbit. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I wonder if anyone has modeled the difference between the two scenarios? Dave -Original Message- From: mixent mix...@bigpond.com To: vortex-l vortex-l@eskimo.com Sent: Sun, Feb 10, 2013 9:32 pm Subject: Re: [Vo]:Near earth asteroid info In reply to David Roberson's message of Sun, 10 Feb 2013 11:45:07 -0500 (EST): Hi, [snip] I think you need to take into account that the Earth is a very tiny target at our distance from the sun. Perhaps you should calculate roughly how much of that CME actually impacts us per unit of surface area. Since it begins as a plasma, it most likely is not dense enough to cause much trouble. Dave This is also the answer to you own previous post. ;) When the pieces are small, the ratio of surface area to volume is much greater than for a single large meteor. That means vastly more friction, and consequently more heat absorbed by the mass of rock, sooner. IOW they vaporize in the upper atmosphere long before they get near the ground. The added friction has another effect too. It tends to spread them out over a larger area. Nevertheless, I imagine it would quite a light show, and the shock wave might still be somewhat dangerous. Furthermore, blowing the thing up while still in space will also spread the pieces over a much larger area by the time they hit the atmosphere, and some of them may either never hit, or not until a following orbit. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
On Sun, Feb 10, 2013 at 7:10 PM, David Roberson dlrober...@aol.com wrote: I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I suspect this is mistaken. Think of the difference between the momentum in a regular bullet, and the same momentum in the same amount of metal, pressed into a very thin foil with a large area. In the limiting case, I think the foil would be mostly harmless. In the example of the meteor versus the dust of the meteor once it has been blown to smithereens, it is the concentration of the momentum that seems most important. Eric
Re: [Vo]:Near earth asteroid info
It just seems to me that 1 CME avg per day x 1.2 Billion Tons/CME x 4.5 Billion Years old x 365 days/year = LOTS OF ordinary STUFF floating around the solar system. Of course I am thinking lots of it is collapsed matter but what do I know. Stewart On Sun, Feb 10, 2013 at 10:14 PM, Eric Walker eric.wal...@gmail.com wrote: On Sun, Feb 10, 2013 at 7:10 PM, David Roberson dlrober...@aol.comwrote: I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I suspect this is mistaken. Think of the difference between the momentum in a regular bullet, and the same momentum in the same amount of metal, pressed into a very thin foil with a large area. In the limiting case, I think the foil would be mostly harmless. In the example of the meteor versus the dust of the meteor once it has been blown to smithereens, it is the concentration of the momentum that seems most important. Eric
Re: [Vo]:Near earth asteroid info
The bullet comparison is a good one to consider. I would think that both momentum and energy would be conserved with the torn apart asteroid. The event in Russia around the turn or the last century could have been caused by this type of behavior on a small scale. It would have been interesting to be beneath that one for a short time. To obtain a good understanding of the damage caused by a broken up asteroid event, you must take into account the energy release. The momentum is not too important for a relatively small impact as compared to the large earth. I think the blast due to the energy release would be the most dangerous part of the episode. Think of the asteroid as one really big atomic weapon if intact or a million smaller ones if broken into a million parts. The mass of a sphere goes up as the cube of the radius so a body several miles in radius would cover a large area with a layer of material if spread out. I have a feeling that the atmosphere would be stripped away by anything of that nature. Dave -Original Message- From: Eric Walker eric.wal...@gmail.com To: vortex-l vortex-l@eskimo.com Sent: Sun, Feb 10, 2013 10:15 pm Subject: Re: [Vo]:Near earth asteroid info On Sun, Feb 10, 2013 at 7:10 PM, David Roberson dlrober...@aol.com wrote: I realized I was preaching to the choir a bit with my broken up asteroid versus one big bad one. But, I actually do think that the total amount of energy deposited into the atmosphere and ground would be the same in either case. If it would destroy all the life on earth as a single hit, I would think it would do the same even if distributed over a large area. The energy is what does the damage. The light show would be most beautiful until the shock wave tore you into pieces. That would be a great way to leave the world! I suspect this is mistaken. Think of the difference between the momentum in a regular bullet, and the same momentum in the same amount of metal, pressed into a very thin foil with a large area. In the limiting case, I think the foil would be mostly harmless. In the example of the meteor versus the dust of the meteor once it has been blown to smithereens, it is the concentration of the momentum that seems most important. Eric
Re: [Vo]:Near earth asteroid info
In reply to de Bivort Lawrence's message of Thu, 7 Feb 2013 23:28:29 -0500: Hi, Wouldn't blowing up an asteroid merely create a lot of smaller pieces raining down on earth, with only a few deflected into non-collision paths. If the pieces are small enough, they will burn up in the atmosphere harmlessly. [snip] Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
This would be true if the pieces came down over a large area and at a moderate number per hour. I suspect that a large mass of individual pieces coming down close together would behave a lot like one big one. The energy contained within the large mass of individual meteorites would be about the same as that in one. Dave -Original Message- From: mixent mix...@bigpond.com To: vortex-l vortex-l@eskimo.com Sent: Sat, Feb 9, 2013 10:51 pm Subject: Re: [Vo]:Near earth asteroid info In reply to de Bivort Lawrence's message of Thu, 7 Feb 2013 23:28:29 -0500: Hi, Wouldn't blowing up an asteroid merely create a lot of smaller pieces raining down on earth, with only a few deflected into non-collision paths. If the pieces are small enough, they will burn up in the atmosphere harmlessly. [snip] Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
Re: [Vo]:Near earth asteroid info
Hi, On 7-2-2013 22:19, Jed Rothwell wrote: I don't know why this is in the Business section. That does not surprise me at all, as it may have an incredible huge impact on the way (some of) the traders may react. Kind regards, Rob
[Vo]:Near earth asteroid info
See: http://neo.jpl.nasa.gov/ http://www.washingtonpost.com/business/150-foot-asteroid-will-buzz-earth-next-week-no-need-to-duck-for-incredibly-close-approach/2013/02/07/29170cf6-715d-11e2-b3f3-b263d708ca37_story.html I don't know why this is in the Business section. Anyway, it is from the AP and it says: CAPE CANAVERAL, Fla. — An asteroid measuring 150 feet will zip past Earth next week. The megarock will pass within 17,000 miles of the planet — the closest known approach ever for an object of this size. But NASA scientists said Thursday there’s no reason to worry. They insist there is absolutely no chance of a collision next Friday. The asteroid — considered small — will come closer to Earth than many high-flying communication satellites. It will be visible through binoculars or telescopes as it zooms by at 17,400 mph. The best viewing location will be Indonesia. Other prime viewing spots are Eastern Europe, Asia and Australia. The asteroid was discovered last February. - Jed
Re: [Vo]:Near earth asteroid info
That is scary! Now I know what it feels like to be just out of range of a mad shooter. I fear that one day he will get lucky and we will have a new problem to solve. If this one was just discovered last February then how many more are waiting on the sidelines? Yipes. Dave -Original Message- From: Jed Rothwell jedrothw...@gmail.com To: vortex-l vortex-l@eskimo.com Sent: Thu, Feb 7, 2013 4:20 pm Subject: [Vo]:Near earth asteroid info See: http://neo.jpl.nasa.gov/ http://www.washingtonpost.com/business/150-foot-asteroid-will-buzz-earth-next-week-no-need-to-duck-for-incredibly-close-approach/2013/02/07/29170cf6-715d-11e2-b3f3-b263d708ca37_story.html I don't know why this is in the Business section. Anyway, it is from the AP and it says: CAPE CANAVERAL, Fla. — An asteroid measuring 150 feet will zip past Earth next week. The megarock will pass within 17,000 miles of the planet — the closest known approach ever for an object of this size. But NASA scientists said Thursday there’s no reason to worry. They insist there is absolutely no chance of a collision next Friday. The asteroid — considered small — will come closer to Earth than many high-flying communication satellites. It will be visible through binoculars or telescopes as it zooms by at 17,400 mph. The best viewing location will be Indonesia. Other prime viewing spots are Eastern Europe, Asia and Australia. The asteroid was discovered last February. - Jed
Re: [Vo]:Near earth asteroid info
David Roberson dlrober...@aol.com wrote: If this one was just discovered last February then how many more are waiting on the sidelines? NASA and others are taking the problem seriously. See their Near-Earth Object Project: http://neo.jpl.nasa.gov/ http://www.spaceguarduk.com/ Part of the credit for this goes to our late friend Arthur Clarke. He coined the term Spaceguard I think, and lobbied for this effort. The first thing to do is to locate as many asteroids as possible. If we have sufficient time I think we can deflect even a large object. I think there is an upper limit to the likely size. I doubt that an object the size of Mt. Everest is likely to appear out of deep space. - Jed
Re: [Vo]:Near earth asteroid info
If we have the ability to deflect large objects, we would probably have the ability simply to nuke them with a 20 megaton bomb and turn them into gravel (presumably). In fact, my vague impression is that we have that ability now or could have it within a decade. A 'spaceguard' of orbiting nukes, at varying distances from the earth, at the orbit of the moon and much farther, would give us the ability to meet the objects at a safe distance from earth. If they are intercepted at a distance far enough from the earth that the earth is, say, 1/1000th of the sphere of space around the object that it 'sees', then the gravel that hits earth would burn up in the atmosphere. Some satellites might be destroyed, but that would be a trade worth making. The scare-movies I have seen about large nukes portray them as having a fireball larger than Manhattan, so I assume they could make mincemeat out of a 1km-wide asteroid; but even if they left several large chunks, the chances of one of the chunks hitting that 1/1000th bit of of the asteroid's sphere would be miniscule. And why not have followup nukes to make smaller chunks out of the larger chunks? As Swift said: a Flea Hath smaller Fleas that on him prey, And these have smaller Fleas to bite 'em, And so proceed ad infinitum
Re: [Vo]:Near earth asteroid info
I believe that the nuclear option is on the table. I think it would be easier to divert the asteroids by digging in the warhead under a large mass of material that can be expelled by the blast. The momentum given to the expelled mass would be matched by that transferred to the remaining asteroid. I visualize a large quantity of water located with the nuclear charge that can be vaporized at the time of the blast, giving a push to the mass that is expelled. I do not know if normal asteroid matter can be vaporized to the required degree, but If it can, leave the water home. Dave -Original Message- From: Vorl Bek vorl@antichef.com To: vortex-l vortex-l@eskimo.com Sent: Thu, Feb 7, 2013 6:52 pm Subject: Re: [Vo]:Near earth asteroid info If we have the ability to deflect large objects, we would probably have the ability simply to nuke them with a 20 megaton bomb and turn them into gravel (presumably). In fact, my vague impression is that we have that ability now or could have it within a decade. A 'spaceguard' of orbiting nukes, at varying distances from the earth, at the orbit of the moon and much farther, would give us the ability to meet the objects at a safe distance from earth. If they are intercepted at a distance far enough from the earth that the earth is, say, 1/1000th of the sphere of space around the object that it 'sees', then the gravel that hits earth would burn up in the atmosphere. Some satellites might be destroyed, but that would be a trade worth making. The scare-movies I have seen about large nukes portray them as having a fireball larger than Manhattan, so I assume they could make mincemeat out of a 1km-wide asteroid; but even if they left several large chunks, the chances of one of the chunks hitting that 1/1000th bit of of the asteroid's sphere would be miniscule. And why not have followup nukes to make smaller chunks out of the larger chunks? As Swift said: a Flea Hath smaller Fleas that on him prey, And these have smaller Fleas to bite 'em, And so proceed ad infinitum
Re: [Vo]:Near earth asteroid info
I have read that it would be difficult to stop rocks with nuclear bombs. It is not practical to fly the bomb at the thing and detonate it the moment they are close, with a proximity fuse. Large, heavy objects often survived above ground nuclear explosions intact. I think no matter what technique you use, you have to land on the rock and then deploy something. If you have plenty of time -- several years let us say -- might as well deploy a bucket of paint or a small laser as a nuclear bomb. It does not take much to change the trajectory. Most of these objects are not big. I think the big ones are all detected and accounted for. The acute danger is one showing up weeks or months before impact. Perhaps a hail Mary nuclear bomb might stop it. I think you would have to land on it, dig a hole, and then use the bomb. That would make the rock resemble a nuclear bomb powered Orion rocket. Landing and deploying a bomb in this manner sounds impossible without a human crew, but the robot explorers on Mars have remarkable abilities. Perhaps in a generation they will be capable of this. - Jed
Re: [Vo]:Near earth asteroid info
On Thu, Feb 7, 2013 at 3:52 PM, Vorl Bek vorl@antichef.com wrote: A 'spaceguard' of orbiting nukes, at varying distances from the earth, at the orbit of the moon and much farther, would give us the ability to meet the objects at a safe distance from earth. I think this would be difficult to arrange for, in light of how challenging it has been for the US and NATO to obtain agreement on missile defense in Eastern Europe. I don't imagine any large country would be happy with powerful nuclear weapons in orbit. Eric
Re: [Vo]:Near earth asteroid info
Wouldn't blowing up an asteroid merely create a lot of smaller pieces raining down on earth, with only a few deflected into non-collision paths. Maybe a better solution would be a space tug, which would go out, hook up the asteroid and begin tugging it out of the collision trajectory. Another matter to consider is just what constitute a non-collision. Could a football field-sized asteroid zip past at a huge speed, say, 50 miles away from earth (technically, still in space) and have no damaging effect on human beings, or on our infrastructure, or on other species? Cheers, Lawry On Feb 7, 2013, at 10:28 PM, Jed Rothwell wrote: I have read that it would be difficult to stop rocks with nuclear bombs. It is not practical to fly the bomb at the thing and detonate it the moment they are close, with a proximity fuse. Large, heavy objects often survived above ground nuclear explosions intact. I think no matter what technique you use, you have to land on the rock and then deploy something. If you have plenty of time -- several years let us say -- might as well deploy a bucket of paint or a small laser as a nuclear bomb. It does not take much to change the trajectory. Most of these objects are not big. I think the big ones are all detected and accounted for. The acute danger is one showing up weeks or months before impact. Perhaps a hail Mary nuclear bomb might stop it. I think you would have to land on it, dig a hole, and then use the bomb. That would make the rock resemble a nuclear bomb powered Orion rocket. Landing and deploying a bomb in this manner sounds impossible without a human crew, but the robot explorers on Mars have remarkable abilities. Perhaps in a generation they will be capable of this. - Jed
