Asteroid Affirmative

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And an asteroid impact can independently cause extinction

Chapman 04 (Clark R., planetary scientist, first editor of Journal of Geophysical Research- Planets, PhD MIT, Frontiers, The hazard of near – Earth asteroid impacts on earth,, Google scholar, NC)

I briefly summarize three scenarios (drawn from many more in [63]), which illustrate the breadth of issues that must be confronted in managing potential consequences of NEA impacts. For each impact disaster scenario, I consider the nature of the devastation, the probability that the event will happen, the likely warning time, the possibilities for post-warning mitigation, the nature of issues to be faced in after-event disaster management, and—of most practical interest—what can be done now to prepare in advance. 6.1. 2–3 km diameter civilization destroyer A million-megaton impact, even though f100 times less energetic than the K–T impact, would probably destroy civilization as we know it. The dominant immediate global effect would be sudden cooling, lasting many months, due to massive injection of dust into the stratosphere following impact. Agriculture would be largely lost, worldwide, for an entire growing season. Combined with other effects (a firestorm the size of India, destruction of the ozone layer, etc.), it is plausible that billions might die from collapse of social and economic institutions and infrastructure. No nation could avoid direct, as well as indirect, consequences of unprecedented magnitude. Of course, because civilization has never witnessed such an apocalypse, predictions of consequences are fraught with uncertainty. As discussed earlier, few bodies of these sizes remain undiscovered, so the chances of such an event are probably < 1-in-100,000 during the next century. The warning time would almost certainly be long, in the case of a NEA, but might be only months in the case of a comet. With years or decades of advance warning, a technological mission might be mounted to deflect the NEA so that it would miss the Earth; however, moving such a massive object would be very challenging. In any case, given sufficient warning, many immediate fatalities could be avoided by evacuating ground zero and longer-term casualties could be minimized by storing food supplies to survive the climate catastrophe. Susceptible infrastructure (transportation, communications, medical services) could be strengthened in the years before impact. However, no preparation for mitigation is warranted for such a rare possibility until a specific impact prediction is made and certified. The only advance preparations that might make sense would be at the margins of disaster planning developed for other purposes: considering such an apocalypse might foster ‘‘out of- the-box’’ thinking about how to define the outer envelope of disaster contingencies, and thus prove serendipitously useful as humankind faces an uncertain future. 6.2. Once-in-a-century mini-Tunguska atmospheric explosion Consider a 30–40-m office-building-sized object striking at 100 times the speed of a jetliner. It would explode f15 km above ground, releasing the energy of f100 Hiroshima-scale bombs. Weak structures would be damaged or destroyed by the blast wave out to 20 km. The death toll might be hundreds; although casualties would be far higher in a densely populated place, they would much more likely be zero (i.e., if the impact were in the ocean or a desolate location). Such an event is likely to occur in our grandchildren’s lifetime, although most likely over the ocean rather than land. Even with the proposed augmented Spaceguard Survey, it is unlikely that such a small object would be discovered in advance; impact would occur without warning. Since it could occur literally anywhere, there are no location- specific kinds of advance measures that could or should be taken, other than educating people (perhaps especially military forces that might otherwise mistake the event as an intentional attack) about the possibilities for such atmospheric explosions. In the lucky circumstance that the object is discovered years in advance, a relatively modest space mission could deflect such a small body, preventing impact [26


Scenario: Ocean Strike

Asteroid is likely to hit the ocean – creates huge tsunami waves, according to computer simulations.

Stephens 03 (Tim, Staff Writer @ UC Santa Cruz, “Massive tsunami sweeps Atlantic Coast in asteroid impact scenario for March 16, 2880” May 27, 2003) JM

If an asteroid crashes into the Earth, it is likely to splash down somewhere in the oceans that cover 70 percent of the planet's surface. Huge tsunami waves, spreading out from the impact site like the ripples from a rock tossed into a pond, would inundate heavily populated coastal areas. A computer simulation of an asteroid impact tsunami developed by scientists at the University of California, Santa Cruz, shows waves as high as 400 feet sweeping onto the Atlantic Coast of the United States. The researchers based their simulation on a real asteroid known to be on course for a close encounter with Earth eight centuries from now. Steven Ward, a researcher at the Institute of Geophysics and Planetary Physics at UCSC, and Erik Asphaug, an associate professor of Earth sciences, report their findings in the June issue of the Geophysical Journal International

Tsunami caused by asteroid would collapse the global economy

Gilster 07(Paul Gilster is the author of “Centauri Dreams: Imagining and Planning Interstellar Exploration” and writer for the Tau Zero Foundation. “Sizing up the Asteroid Threat”, April 3 2007,, TDA)

Indeed, while a 100 meter asteroid could cause relatively localized damage across several countries, doubling the object to 200 meters causes tsunamis on a global scale, assuming an oceanic hit. In terms of casualties, the study sees China, Indonesia, India, Japan and the US as the most vulnerable, though obviously a direct hit on any heavily populated area would be catastrophic. Economically speaking, where the infrastructure is tells much of the tale. Put dense development along the coastlines of economically prosperous areas and you open yourself to the threat of tsunamis and earthquakes emmanating from a wide variety of impact areas. Sweden’s long coastline thus places it in high danger economically, while an impact in the north Atlantic could send devastating tsunamis into both Europe and America. Severe economic effects would clearly result from a strike involving China or Japan. Although we’re currently engaged through projects like the Spaceguard survey in cataloguing NEOs larger than one kilometer in diameter, the smaller objects represented in the Southampton study are largely undetected. The risk of being blindsided by such an object emphasizes our need to develop a space-based observation platform for tracking asteroids of this size, along with providing more accurate information about the movements of larger Earth crossers. Bailey again: “The threat of the Earth being hit by an asteroid is increasingly being accepted as the single greatest natural disaster hazard faced by humanity.”

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