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- NW Fail – Standoff blast fails
- Stand-off blast will be absorbed
- Standoff blast carries the same risk as a direct strike
Frag Bad – prevents deflectionFragmentation prevents other forms of deflectionChapman ‘3 (Clark, scientist at the Southwest Research Institute's Department of Space Studies, Great Impact Debates, Collision Course for Earth 3/03 http://www.astrobio.net/index.php?option=com_debate&task=detail&id=389) Clark Chapman: The advantage of using nuclear weapons to destroy asteroids is that they are our most powerful devices by far. But the disadvantages are many. In particular, the more we learn about asteroids and comets, the more we realize that they are incredibly fragile. Most asteroids larger than a few hundred meters across are now thought to be "rubble piles" -- collections of rocks, boulders, and "mountains" simply resting against each other, loosely held together by the tenuous gravitational field of the ensemble. Any sudden force applied to such an object would likely tear it apart into a swarm of objects. The total impacting energy of the swarm would be the same as the original asteroid, but spread out across the Earth's surface. In any case, once you disrupt a comet or asteroid into many different chunks, you've lost all ability to affect what happens next. In short, it is a very bad idea. NW Fail – Standoff blast failsStand-off blast failsSchweickart ‘4 (Russell, Chair of the B612 Foundation, former astronaut, Executive Vice President of CTA Commercial Systems, Inc. and Director of Low Earth Orbit (LEO) Systems and research, and scientist at the Experimental Astronomy Laboratory of the Massachusetts Institute of Technology (MIT), “Asteroid Deflection; Hopes and Fears,” Aug., Presented at the World Federation of Scientists Workshop on Planetary Emergencies, Erice, Sicily, August 2004 http://www.b612foundation.org/papers/Asteroid_Deflection.doc) The hard options consist of various forms of nuclear explosion as well as that of direct (or kinetic) impact. In each case, however, to be effective the resultant force must be applied along the NEA’s velocity vector, with the exception of two cases. If one considers the option of fragmenting the NEA a viable option (i.e., blowing it to pieces) then the direction of impulse becomes meaningless. While there are many uncertainties regarding the effect of a nuclear explosion intended to fragment an asteroid (generally assumed to be a sub-surface burst) it seems clear that, given a large enough nuclear weapon, the fragmentation could be achieved. Arguments have been made from the first discussion of this option, however, that such a strategy would be unwise since the possibility exists that the resultant fragmentation could actually increase the overall threat and not eliminate it. No general answer to this debate will likely evolve since it is highly dependent on the structural character of the asteroid in question. The more favored nuclear options are intended not to fragment the asteroid but rather to accelerate it in a preferred direction adequate to cause it to miss its rendezvous with Earth. While quite distinct in specifics two examples serve to illustrate the options here. One a surface burst designed to excavate asteroidal materials and eject them in a preferred direction. Alternatively a stand-off explosion, probably maximizing the neutron flux directed at the surface of the asteroid to cause an explosive boil-off of the surface to generate the desired impulse. In both these cases the characteristics of the specific asteroid are clearly critical. In addition to this uncertainty the placement of the nuclear explosive in each case must be quite precise in order for the resultant impulse to be generated in the desired direction. The certainty of such a placement is profoundly enhanced if the explosive it positioned by a spacecraft which has fully rendezvoused with the asteroid; i.e., if the spacecraft has matched velocity with the asteroid. Such a rendezvous however, requires considerable fuel compared with a flyby where the spacecraft simply flys by at a precise distance at high speed and the nuclear warhead explodes at precisely the correct time. The cumulative uncertainties intrinsic in this design, combined with the unknowns about the structural characteristics of asteroids lead many proponents of deflection to remain skeptical about the nuclear options. Stand-off blast will be absorbedFountain ‘2 (Henry, New York Times correspondent, Armageddon Can Wait: Stopping Killer Asteroids, November 19, http://www.nytimes.com/2002/11/19/science/space/19ASTE.html) But it is becoming clear that a longtime assumption of many scientists ? and of Hollywood filmmakers ? that a nuclear weapon is the best way to save the planet from a threatening asteroid is no longer in such favor. Increasingly, those scientists who study asteroid hazards say that a subtler, quieter, slower approach might be called for. These scientists are turning T. S. Eliot on his head: it's not that the world will end with a whimper rather than a bang, they say. It's that it may not end that way. A nuclear detonation, some scientists say, could break the asteroid into several large pieces, increasing, rather than eliminating, the threat. And a blast some distance from an asteroid, designed to shove it into a slightly different orbit, might not work either; the asteroid might soak up the energy like a sponge. "I'd say forget that," said Dr. Keith A. Holsapple, a professor at the University of Washington who studies the effects of simulated nuclear explosions. By contrast, most of the alternative approaches would build up force gradually, gently nudging, rather than shoving, the asteroid. They would rely on the same basic Newtonian principle ? that for every action there is an equal and opposite reaction ? only written small, with tiny actions creating tiny opposite reactions that, given enough time, could shift an asteroid's orbit enough to change a hit into a close call. Standoff blast carries the same risk as a direct strikeMerali ‘5 (Zeeya, PhD in physics, New Scientist, lexis) WHEN it comes to deflecting an asteroid that is on a collision course with Earth, "most people think of the Hollywood treatment – throw a nuclear weapon at it", says NASA astronaut Edward Lu. "That's the blast-and-hope strategy." It is hard to predict where the shattered pieces would go, and many smaller chunks might still head towards Earth. Now Lu and fellow astronaut Stanley Love at NASA's Johnson Space Center in Houston, Texas, have come up with the simplest – and least glamorous – solution yet: park a heavy spacecraft near the asteroid and use gravity as an invisible towline to tug the rock off its deadly course. Other ideas for dealing with such threats have included detonating nuclear bombs near the asteroid – rather than nuking it directly – to nudge it off track. But this carries the same risks as shattering the asteroid. Some have advocated painting the asteroid white to change the amount of solar energy it reflects, thus altering the forces acting upon it and hopefully changing its course. However, the sheer amount of paint this would require makes it impractical, says Lu. Directory: files files -> Answer True False 2 points Question 2 files -> Integer programming and game theory files -> 4 Integer Programming files -> Bpa vehicle Window Repair Scenario #1 task: Procure vehicle window relacement. Objective files -> Pop Warner History files -> North Carolina Inclusion Initiative Mapping Where Children with ieps are Being Served Purpose files -> Fall 2013 Spring 2014 Program Data: Standard 1 Exhibit 4d files -> Hanban – asia society confucius classrooms network 2010 request for proposal files -> Northern England’s set-jetting locations Download 1.03 Mb. Share with your friends:
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