Evaluation of the Asteroid Impact Hazard, 15-9130Printer Friendly Version
Inclusive Dates: 03/30/99 - 01/31/01
Background - The nation and the world are on the threshold of deciding what to do about what is called Planetary Defense: how do we address the rare but horrific possibility that civilization might end because of the impact of a mile-wide asteroid or comet? Currently SwRI has several leading researchers who have been engaged in this recently discovered threat, and the Institute has much latent talent that could be brought to bear on mitigating the threat when the nation decides to proceed. During this transitional time, SwRI staff members are helping to shape the decisions of federal agencies and international bodies about how to address the impact threat by engaging in several research efforts designed to advance the world's understanding of the impact hazard, its relationship to other natural hazards, and approaches to mitigating catastrophe should a dangerous asteroid or comet be found to be heading toward Earth. At the end of this modest project, the team intended for the Institute to be well positioned to help society address this threat in a responsible way. The research team believes those objectives have been met.
Approach - While plans for telescopic searches for threatening asteroids and comets are well advanced, SwRI performed complementary research to identify the significance of discoveries, realistic error bars in impact or "near miss" predictions, and proper ways to characterize such predictions in order for policy- and decision-makers to respond appropriately (e.g., development of a useful Impact Hazard Index, analogous to the Richter Scale for earthquakes). These research activities were conducted in the context of the team's current and invited participation in activities of the International Astronomical Union Working Group on Near Earth Objects, the June 1999 NASA/ESA/IAU IMPACT Workshop in Torino, and the Prediction Science project sponsored by the Geological Society of America and the National Center for Atmospheric Research. Also the team analyzed impact rates as a function of size, refined estimates of the expected environmental and societal damage due to an impact, and comparatively evaluated the impact hazard with other natural hazards to place the impact hazard in a proper context within the natural hazards research community. Finally, collaborating with Robert Gold of Johns Hopkins Applied Physics Laboratory, the team developed a broad, end-to-end analysis of approaches to the NEO hazard and mitigation, which was summarized in an SwRI "white paper" that received wide national and international attention last spring. It continues to be a widely read roadmap for how society should deal with the impact threat.
Accomplishments - All phases of this research were completed prior to FY2001, except for work on the white paper by Chapman and Durda, in collaboration with Gold. The report, dated 24 February 2001, is entitled "The Comet/Asteroid Impact Hazard: A Systems Approach," and it may be found at www.boulder.swri.edu/clark/neowp.html (a link to a professionally formatted version is found at the top of this link). The publication of the report was picked up by the news media, especially the Associated Press, and was prominently featured in newspapers around the country. The SwRI white paper was also featured among background material used by the 2001 United Nations/AIAA/CEAS/IAA Workshop on International Space Cooperation (see report on "An International Approach to Detecting Earth-Threatening Asteroids and Comets and Responding to the Threat They Pose" at www2.aiaa.org/international/information/PDF/ISCW-6-report.pdf). On May 8, Chapman gave a public presentation of the report findings at the SwRI Videoconferencing Center at the San Antonio facility, reporting findings from the research effort. The findings were also reported at the NASA Aerospace Technology Working Group meeting on May 15. Durda discussed the report with General Simon Worden of the Air Force Space Command on October 12, 2001, and Chapman and Durda discussed the report with several astronauts at the Johnson Space Center on October 20, 2001.