Lewis 2k (John S., professor of planetary science at the University of Arizona’s Lunar and Planetary Laboratory, “Comet and Asteroid Impact Hazards a Populated Earth”, Print)//DT
The expected economic losses from impact events are discussed by Canavan et al. (1994) in the context of a statistically averaged impact flux model. Their differential loss curves for impacts consist of four straight-line segments on a log (loss) vs. log (mass) plot, with abrupt discontinuities of a factor of 20-50 between adjacent segments. An impact model that takes into account the full statistical variability of initial orbital parameters, entry conditions, impactor physical properties, and impact site, such as the present Monte Carlo model, does not exhibit such discontinuous behavior. A more direct way to estimate losses is to realize that the geographical distribution of humans and of human assets are very similar; so much so chat the ratio of fatalities to economic loss is arguably nearly a constant. Our approach, therefore, is to use human casualties as a proxy for economic loss. Note that this approach does not mean assigning a cash value to human life; rather, it is an estimate of the average cash value of property and goods destroyed per human death. Conversion of impact deaths to expected economic loss can be achieved to adequate accuracy by multiplying the number of deaths by a constant. A comparison of Canavan's cost analysis with the lethality' predictions or. Morrison etaL (1994) or with the present work suggests a conversion factor of about $100,000 per person. This factor in turn suggests that a mid-2 Oth-century global population of 5 X 109 people would have a total property value of $5 X 1014, which, at a gross global product level of about S2.5 X 10" per year, represents about 20 years of global product. This seems a reasonable estimate. Therefore an analysis that suggests an expected time-averaged fatality rate of 3000 people per year would likewise suggest an expected mean direct economic (property) loss of about $300 million per year, in accord with Canavan's estimate. A global insurance policy against impacts with premiums of $100 million a year would be an excellent bargain. Over the long term, an insurance company offering such coverage would have to charge premiums of at least $400 million per year to remain in business. Thus any combination of prevention and remediation costs (discover, tracking, characterization, interception, and diversion) costing $100 million would pay back that investment several times over. We shall return to this issue in Chapter 8. It should he amply evident, however, that a true global catastrophe that prevents agriculture for a year or otherwise destroys the infrastructure of civilization (including all insurance companies) is not an acceptable outcome no matter how much insurance we may earn'.
Even a small asteroid strike destroys the economy
Ames Research Center 2003 - NASA’s Ames Research Center is a world-class research facility located in the heart of Silicon Valley. The center is involved with many high-tech projects, ranging from developing small spacecraft to managing some of the world’s largest supercomputers, and conducting astrobiology research (July 8, * Dr. Harrison H. Schmitt * Dr. Carolyn S. Shoemaker * David H. Levy * Dr. John Lewis * Dr. Neil D. Tyson * Dr. Freeman Dyson * Dr. Richard P. Hallion * Dr. Thomas D. Jones * Bruce Joel Rubin * Dr. Lucy Ann McFadden * Erik C. Jones * Marc Schlather * William E. Burrows, “ NASA NEO News: Open Letter to Congress on Near Earth Objects ” http://www.spaceref.com/news/viewsr.html?pid=9866 )
For the first time in human history, we have the potential to protect ourselves from a catastrophe of truly cosmic proportions. All of us remember vividly the effect on our nation of terrorist strikes using subsonic aircraft turned into flying bombs: thousands of our citizens dead, and our economy badly shaken. Consider the ramifications of an impact from a relatively small NEO: more than a million times more massive than an aircraft, and traveling at more than thirty times the speed of sound. If such an object were to strike a city like New York, millions would die. In addition to the staggering loss of life, the effects on the national and global economy would be devastating. Recovery would take decades.
Astronautics, MIT, Association of Space Explorers International Panel on Asteroid Threat Mitigation, “Asteroid Threats: A Call For Global Response”, http://www.space-explorers.org/ATACGR.pdf)//DT
Earth's geological and biological history is punctuated by evidence of repeated and devastating impacts from space. Sixty-five million years ago, an asteroid impact caused the extinction of the dinosaurs along with some 70% of Earth's living species. A more typical recent impact was the 1908 Tunguska Event, a 3-5 megaton explosion which destroyed 2,000 square kilometers of Siberian forest. A future asteroid collision could have disastrous effects on our interconnected human society. The blast, fires, and atmospheric dust produced could cause the collapse of regional agriculture, leading to widespread famine. Ocean impacts like the Eltanin event (2.5 million years ago) produce tsunamis which devastate continental coastlines. Asteroid 99942 Apophis, which has a 1-in-45,000 chance of striking Earth in 2036, would generate a 500-megaton (MT) blast and inflict enormous damage. Devastating impacts are clearly infrequent events compared to a human lifetime: Tunguska, thought to be caused by the impact of a 45-meter-wide asteroid, is an event that occurs on average two or three times every thousand years. However, when Near Earth Object (NEO) impacts occur they can cause terrible destruction, dwarfing that caused by more familiar natural disaster.