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IMPACT HAZARDS: TRUTH AND CONSEQUENCES
"Article By Gerrit L. Verschuur"
I believe that the most significant longterm consequence of the discovery of the cosmic impact threat, assuming we avoid destruction, will probably involve the increased awareness on the part of Earth's inhabitants of our shared vulnerability in the cosmos. It is difficult enough to accept the inevitability of personal mortality, but it is virtually impossible to imagine that an impact event could wipe the planet clean of all human beings in a matter of weeks. But once we begin to take this
possibility seriously, will not our view of ourselves in the cosmic scheme of things inevitably change?
Benny Peiser (Liverpool John Moores University) recently organized a conference on the disappearance of the Bronze Age
civilizations, which occurred in three distinct episodes between 2500 and 800 B.C. Evidence is accumulating that impact
events may have been the cause. He observes that some people involved in NEO (Near Earth Objects) research tend to be very conservative in uttering warnings about the future. He explains, "Scientists who wish to be truthful to interested laypeople and the general public, should readily admit that mankind will continue to live in a world of cosmic uncertainties as long as we fail to spend more time, more research, and much more money on gathering the vital information which is not only necessary for any tenable calculation of impact probabilities but moreover, for the establishment of a global system of planetary defense.
I suspect that we will be prepared to survive the next major impact only if we overcome human nature. In order for civilization to continue to evolve we must take responsibility for our destiny. We must define the NEO hazard precisely by charting where every NEO is at all times and, when threatened, take steps to avoid an impact by whatever means are then at
our disposal.
Consider that communities all over the world live happily on the sides of volcanoes, atop active geologic faults, in the central United States "tornado alley," and along the hurricane-prone Atlantic coast. These are all manifestations of the syndrome that human nature does not allow us to take seriously a low probability, high-consequence risk -- a trait that may
someday spell the extinction of civilization, and probably of our species.
As Peiser says, by learning to turn away NEOs, and the threat they pose to civilization, humans have acquired the capability to change the course of nature and halt the vicious cycle of cosmic cataclysms. Scientists have the responsibility to take this challenge head-on and to ensure that humankind takes its fate into its own hands.
Until a medium-to-large NEO is found that deserves a Hazard Index of 4 to 5, asteroid hunters will do well to consider how the results of their searches are reported to the public. While predictions of future visits should be framed to avoid undue
alarm or panic, the role of the asteroid hazard in the long-term future of a technological civilization on this vulnerable planet
should not be underplayed either.